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Sample records for c91 test projectile

  1. EMGWS, D1 projectile tests

    International Nuclear Information System (INIS)

    This paper reports on the 90 mm EMGWS D1 Projectile which is an unguided projectile that is designed for launch from an Electromagnetic gun to achieve significant armor penetration. It is being developed under the broader program called Electromagnetic Gun Weapon System (EMGWS) which is sponsored by DARPA, DNA, and the U.S. Army. The 90 mm D1 Type II 'workhorse' Projectile is used to prove out material strength, fabrication techniques, and projectile structural integrity. The type II flight projectile is designed to allow maximum stress levels of 100-ksi when launched at 100-kilogees peak acceleration. The total weight of the projectile is 2.0 kg to attain a muzzle velocity of 3.0 km/s from a 9-Megajoule EM Gun. The Type II projectile configuration employs a tungsten nosetip plus 12 segmented tungsten penetrators, a two-piece aluminum discarding sabot, an aluminum pusher plate, and a nylon obturator. The pusher plate can incorporate either a solid or plasma armature

  2. Design and testing of high-pressure railguns and projectiles

    Science.gov (United States)

    Peterson, D. R.; Fowler, C. M.; Cummings, C. E.; Kerrisk, J. F.; Parker, J. V.; Marsh, S. P.; Adams, D. F.

    1984-03-01

    Attention is given to the results of high-pressure tests involving four railgun designs and four projectile types. Explosive magnetic-flux compression generators were employed to power the railguns. On the basis of the experimental data, it appears that the high-strength projectiles have lower resistance to acceleration than low-strength projectiles, which expand against the bore during acceleration. While confined in the bore, polycarbonate projectiles can be subjected to pressures as high as 1.3 GPa without shattering. In multishot railguns, it is important to prevent an accumulation of sooty material from the plasma armature in railgun seams.

  3. Lightweight Exoatmospheric Projectile (LEAP) test program. Supplemental environmental assessment

    Science.gov (United States)

    1992-06-01

    The proposed action is to modify previously planned Lightweight Exoatmospheric Projectile (LEAP) Test Program activities (LEAP EA, July 1991, Ref 32) at White Sands Missile Range (WSMR), New Mexico; Kwajalein Missile Range (KMR), U.S. Army Kwajalein Atoll (USAKA); and Wake Island. The proposed action includes modifications of flight trajectories for LEAP flights 3, 5, and 6. Two additional flights, LEAP-X and LEAP-7 have been added to the program. LEAP-X is a single rocket test flight from KMR and LEAP-7 is a two-rocket test flight from KMR and Wake Island. Component/assembly ground tests will take place at Orbital Sciences Corporation (OSC), Space Data Division (SDD), Chandler, Arizona; Phillips Laboratory, Edwards Air Force Base, California; Rocketdyne Division of Rockwell International; Boeing Aerospace and Electronics, Kent, Washington; Hughes Aircraft Corporation, Missile Systems Group, Canoga Park California; Aerojet, Sacramento, California; and Thiokol Corporation, Elkton, Maryland.

  4. Design of an Impact Test for Estimating the Deformation Energies of Projectiles in Wound Ballistics Studies

    OpenAIRE

    M. Jauhari; Bandyopadhyay, A

    1980-01-01

    The paper suggests an impact test which can be used to evaluate the deformation energies of small arm projectiles. Such an evaluation is of significance in wound ballistics studies while determining the amount of energy actually consumed in causing cavitation. Various sources of error inherent in the test have been discussed and it has been concluded that although approximate, the test can serve the useful purpose of providing a basis for interpreting the energy loss figures in gel on a ratio...

  5. Determine ISS Soyuz Orbital Module Ballistic Limits for Steel Projectiles Hypervelocity Impact Testing

    Science.gov (United States)

    Lyons, Frankel

    2013-01-01

    A new orbital debris environment model (ORDEM 3.0) defines the density distribution of the debris environment in terms of the fraction of debris that are low-density (plastic), medium-density (aluminum) or high-density (steel) particles. This hypervelocity impact (HVI) program focused on assessing ballistic limits (BLs) for steel projectiles impacting the enhanced Soyuz Orbital Module (OM) micrometeoroid and orbital debris (MMOD) shield configuration. The ballistic limit was defined as the projectile size on the threshold of failure of the OM pressure shell as a function of impact speeds and angle. The enhanced OM shield configuration was first introduced with Soyuz 30S (launched in May 2012) to improve the MMOD protection of Soyuz vehicles docked to the International Space Station (ISS). This test program provides HVI data on U.S. materials similar in composition and density to the Russian materials for the enhanced Soyuz OM shield configuration of the vehicle. Data from this test program was used to update ballistic limit equations used in Soyuz OM penetration risk assessments. The objective of this hypervelocity impact test program was to determine the ballistic limit particle size for 440C stainless steel spherical projectiles on the Soyuz OM shielding at several impact conditions (velocity and angle combinations). This test report was prepared by NASA-JSC/ HVIT, upon completion of tests.

  6. Design of an Impact Test for Estimating the Deformation Energies of Projectiles in Wound Ballistics Studies

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1980-04-01

    Full Text Available The paper suggests an impact test which can be used to evaluate the deformation energies of small arm projectiles. Such an evaluation is of significance in wound ballistics studies while determining the amount of energy actually consumed in causing cavitation. Various sources of error inherent in the test have been discussed and it has been concluded that although approximate, the test can serve the useful purpose of providing a basis for interpreting the energy loss figures in gel on a rational and scientific basis.

  7. LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN

    International Nuclear Information System (INIS)

    Characterization of the reaction violence of LX-04 explosive (85% HMX and 15% Viton A by weight) was obtained from Steven Impact Tests performed above the reaction initiation threshold. A 155 mm Howitzer propellant driven gas gun was used to accelerate the Steven Test projectiles in the range of approximately 170-300 m/s to react (ignite) the LX-04 explosive. Blast overpressure gauges, acoustic microphones, and high-speed photography characterized the level of high explosive reaction violence. A detonation in this velocity range was not observed and when comparing these results (and the Susan test results) with that of other HMX based explosives, LX-04 has a more gradual reaction violence slope as the impact velocity increases. The high binder content (15%) of the LX-04 explosive is believed to be the key factor to the lower level of violence

  8. LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Switzer, L L; Tarver, C M

    2005-07-18

    Characterization of the reaction violence of LX-04 explosive (85% HMX and 15% Viton A by weight) was obtained from Steven Impact Tests performed above the reaction initiation threshold. A 155 mm Howitzer propellant driven gas gun was used to accelerate the Steven Test projectiles in the range of approximately 170-300 m/s to react (ignite) the LX-04 explosive. Blast overpressure gauges, acoustic microphones, and high-speed photography characterized the level of high explosive reaction violence. A detonation in this velocity range was not observed and when comparing these results (and the Susan test results) with that of other HMX based explosives, LX-04 has a more gradual reaction violence slope as the impact velocity increases. The high binder content (15%) of the LX-04 explosive is believed to be the key factor to the lower level of violence.

  9. Experimental Tests of the Proportionality of Aerodynamic Drag to Air Density for Supersonic Projectiles

    CERN Document Server

    Courtney, Elya; Courtney, Michael

    2015-01-01

    Pure theory recognizes the dependence of supersonic drag coefficients on both Mach number and Reynolds number, which includes an implicit dependence of drag coefficient on air density. However, many modern approaches to computing trajectories for artillery and small arms treat drag coefficients as a function of Mach number and assume no dependence on Reynolds number. If drag force is strictly proportional to air density for supersonic projectiles (as suggested by applied theory), the drag coefficient should be independent of air density over a range of Mach numbers. Experimental data to directly support this are not widely available for supersonic projectiles. The experiment determined drag on a 2.59 g projectile from M1.2 to M2.9 using optical chronographs to measure initial and final velocities over a separation of 91.44 m. The free flight determination of drag coefficients was performed at two significantly different atmospheric densities (0.93 kg/m3 and 1.15 kg/m3 ). This experiment supported direct propo...

  10. Results of field testing with the FightSight infrared-based projectile tracking and weapon-fire characterization technology

    Science.gov (United States)

    Snarski, Steve; Menozzi, Alberico; Sherrill, Todd; Volpe, Chris; Wille, Mark

    2010-04-01

    This paper describes experimental results from recent live-fire data collects that demonstrate the capability of a prototype system for projectile detection and tracking. This system, which is being developed at Applied Research Associates, Inc., under the FightSight program, consists of a high-speed thermal camera and sophisticated image processing algorithms to detect and track projectiles. The FightSight operational vision is automated situational intelligence to detect, track, and graphically map large-scale firefights and individual shooting events onto command and control (C2) systems in real time (shot location and direction, weapon ID, movements and trends). Gaining information on enemy-fire trajectories allows educated inferences on the enemy's intent, disposition, and strength. Our prototype projectile detection and tracking system has been tested at the Joint Readiness Training Center (Ft Polk, LA) during live-fire convoy and mortar registration exercises, in the summer of 2009. It was also tested during staged military-operations- on-urban-terrain (MOUT) firefight events at Aberdeen Test Center (Aberdeen, MD) under the Hostile Fire Defeat Army Technology Objective midterm experiment, also in the summer of 2009, where we introduced fusion with acoustic and EO sensors to provide 3D localization and near-real time display of firing events. Results are presented in this paper that demonstrate effective and accurate detection and localization of weapon fire (5.56mm, 7.62mm, .50cal, 81/120mm mortars, 40mm) in diverse and challenging environments (dust, heat, day and night, rain, arid open terrain, urban clutter). FightSight's operational capabilities demonstrated under these live-fire data collects can support closecombat scenarios. As development continues, FightSight will be able to feed C2 systems with a symbolic map of enemy actions.

  11. Electromagnetic diagnostic techniques for hypervelocity projectile detection, velocity measurement, and size characterization: Theoretical concept and first experimental test

    Science.gov (United States)

    Uhlig, W. Casey; Heine, Andreas

    2015-11-01

    A new measurement technique is suggested to augment the characterization and understanding of hypervelocity projectiles before impact. The electromagnetic technique utilizes magnetic diffusion principles to detect particles, measure velocity, and indicate relative particle dimensions. It is particularly suited for detection of small particles that may be difficult to track utilizing current characterization methods, such as high-speed video or flash radiography but can be readily used for large particle detection, where particle spacing or location is not practical for other measurement systems. In this work, particles down to 2 mm in diameter have been characterized while focusing on confining the detection signal to enable multi-particle characterization with limited particle-to-particle spacing. The focus of the paper is on the theoretical concept and the analysis of its applicability based on analytical and numerical calculation. First proof-of-principle experimental tests serve to further validate the method. Some potential applications are the characterization of particles from a shaped-charge jet after its break-up and investigating debris in impact experiments to test theoretical models for the distribution of particles size, number, and velocity.

  12. Investigation on the Artificial Bird Projectile used in Bird Strike Test%用于鸟撞试验的仿真鸟弹研究

    Institute of Scientific and Technical Information of China (English)

    刘小川; 郭军; 孙侠生; 陈建新; 张建军; 苗娟

    2012-01-01

    An artificial bird projectile used in aircraft structure against bird strike experiment was developed. Its basic compositions are gelatine and water. Density is a key parameter controlled by special manufacturing process and adding quenched and tempered materials. The dimension and weight of artificial bird projectile are guaranteed by the mold. Thus, a 1. 8kg standard form of bird projectile was manufactured to meet the regulatory requirements. Three real bird strike tests and one artificial bird strike comparative test were carried out. The target is four aluminium plates with 12mm thickness. Results show that the artificial bird projectile has sufficient strength and can withstand launch overload. The dynamic deformation mode and the dynamic strain response time history of structure of artificial bird projectile are basicly consistent with real bird. The maximum difference of structure dynamic strain response is only 3. 2%; while the difference of structure residual deformation is 8. 7%. Above results prove that the artificial bird projectile developed in this paper can substitute real bird in bird strike experiment.%对用于飞机结构抗鸟撞试验的仿真鸟弹进行了研究,给出了配方,其基体材料为明胶和水.密度是仿真鸟弹的关键参数,通过工艺流程和添加调质材料对其进行控制.鸟弹外形尺寸和重量由模具保证,制作出了满足规范要求的1.8kg标准形态鸟弹.利用4块12mm厚的铝板,进行了3次真实鸟弹试验和1次仿真鸟弹的鸟撞对比试验.试验结果表明,仿真鸟弹具有足够的强度可承受发射过载.同时仿真鸟弹与真实鸟弹的动态变形模式以及结构动态应变响应时间历程基本一致.其结构动态应变响应最大值仅相差3.2%,而结构残余变形相差8.7%.上述结果证明了本文研制的仿真鸟弹可以在结构抗鸟撞试验研究中替代真实鸟弹.

  13. The EMET railgun projectile

    Energy Technology Data Exchange (ETDEWEB)

    Burton, R.L.; Witherspoon, F.D.; Goldstein, S.A. (Gruy Federal, Inc., Arlington, VA (United States))

    1991-01-01

    This paper reports on the EMET projectile which uses joule heating to accelerate the projectile in a railgun with a predominantly electrothermal driving force. The structure is designed to conduct armature current within a thin annular band around the shank of the large L/D dumbbell-shaped projectile. Current is initiated by a fuse located around the shank, and an impedance of 8 m{Omega} is achieved, compared to the 1-2 m{Omega} observed for EM guns. A supersonic nozzle in the projectile tail section expands and cools the armature plasma to raise its resistivity, prevent secondary arcs and provide additional accelerating thrust. Experimental data is presented for 9.5 mm diameter, 5 gm projectiles, accelerated to nearly 600 m/sec at 55 kA in a 0.9 m railgun. The armature remains confined in the projectile structure, and 75% of the acceleration is provided electrothermally.

  14. Small caliber guided projectile

    Science.gov (United States)

    Jones, James F.; Kast, Brian A.; Kniskern, Marc W.; Rose, Scott E.; Rohrer, Brandon R.; Woods, James W.; Greene, Ronald W.

    2010-08-24

    A non-spinning projectile that is self-guided to a laser designated target and is configured to be fired from a small caliber smooth bore gun barrel has an optical sensor mounted in the nose of the projectile, a counterbalancing mass portion near the fore end of the projectile and a hollow tapered body mounted aft of the counterbalancing mass. Stabilizing strakes are mounted to and extend outward from the tapered body with control fins located at the aft end of the strakes. Guidance and control electronics and electromagnetic actuators for operating the control fins are located within the tapered body section. Output from the optical sensor is processed by the guidance and control electronics to produce command signals for the electromagnetic actuators. A guidance control algorithm incorporating non-proportional, "bang-bang" control is used to steer the projectile to the target.

  15. Projectile Demilitarization Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Projectile Wash Out Facility is US Army Ammunition Peculiar Equipment (APE 1300). It is a pilot scale wash out facility that uses high pressure water and steam...

  16. Projectile Motion Demonstration

    Science.gov (United States)

    Graf, Erlend H.

    2008-12-01

    For a recent lecture, I went to our apparatus stock room and took out our venerable Sargent-Welch projectile apparatus that demonstrates that a dropped ball and a horizontally launched ball hit the floor at the same time, if they are simultaneously released. A problem with this apparatus is that its small size makes it difficult for a large class to see what is going on. Furthermore, the projectiles are ball bearings, which tend to roll under chairs, benches, etc.

  17. Hydrodynamic Drag on Streamlined Projectiles and Cavities

    KAUST Repository

    Jetly, Aditya

    2016-04-19

    The air cavity formation resulting from the water-entry of solid objects has been the subject of extensive research due to its application in various fields such as biology, marine vehicles, sports and oil and gas industries. Recently we demonstrated that at certain conditions following the closing of the air cavity formed by the initial impact of a superhydrophobic sphere on a free water surface a stable streamlined shape air cavity can remain attached to the sphere. The formation of superhydrophobic sphere and attached air cavity reaches a steady state during the free fall. In this thesis we further explore this novel phenomenon to quantify the drag on streamlined shape cavities. The drag on the sphere-cavity formation is then compared with the drag on solid projectile which were designed to have self-similar shape to that of the cavity. The solid projectiles of adjustable weight were produced using 3D printing technique. In a set of experiments on the free fall of projectile we determined the variation of projectiles drag coefficient as a function of the projectiles length to diameter ratio and the projectiles specific weight, covering a range of intermediate Reynolds number, Re ~ 104 – 105 which are characteristic for our streamlined cavity experiments. Parallel free fall experiment with sphere attached streamlined air cavity and projectile of the same shape and effective weight clearly demonstrated the drag reduction effect due to the stress-free boundary condition at cavity liquid interface. The streamlined cavity experiments can be used as the upper bound estimate of the drag reduction by air layers naturally sustained on superhydrophobic surfaces in contact with water. In the final part of the thesis we design an experiment to test the drag reduction capacity of robust superhydrophobic coatings deposited on the surface of various model vessels.

  18. Subcaliber discarding sabot airgun projectiles.

    Science.gov (United States)

    Frank, Matthias; Schönekeß, Holger; Herbst, Jörg; Staats, Hans-Georg; Ekkernkamp, Axel; Nguyen, Thanh Tien; Bockholdt, Britta

    2014-03-01

    Medical literature abounds with reports on injuries and fatalities caused by airgun projectiles. While round balls or diabolo pellets have been the standard projectiles for airguns for decades, today, there are a large number of different airgun projectiles available. A very uncommon--and until now unique--discarding sabot airgun projectile (Sussex Sabo Bullet) was introduced into the market in the 1980s. The projectile, available in 0.177 (4.5 mm) and 0.22 (5.5 mm) caliber, consists of a plastic sabot cup surrounding a subcaliber copper-coated lead projectile in typical bullet shape. Following the typical principle of a discarding sabot projectile, the lightweight sabot is supposed to quickly loose velocity and to fall to the ground downrange while the bullet continues on target. These sabot-loaded projectiles are of special forensic interest due to their non-traceability and ballistic parameters. Therefore, it is the aim of this work to investigate the ballistic performance of these sabot airgun projectiles by high-speed video analyses and by measurement of the kinetic parameters of the projectile parts by a transient recording system as well as observing their physical features after being fired. While the sabot principle worked properly in high-energy airguns (E > 17 J), separation of the core projectile from the sabot cup was also observed when discharged in low-energy airguns (E < 7.5 J). While the velocity of the discarded Sussex Sabo core projectile was very close to the velocity of a diabolo-type reference projectile (RWS Meisterkugel), energy density was up to 60 % higher. To conclude, this work is the first study to demonstrate the regular function of this uncommon type of airgun projectile. PMID:24263305

  19. Projectile-Borne Video Reconnaissance System

    Institute of Scientific and Technical Information of China (English)

    王海福; 张锋; 李向荣

    2004-01-01

    Aiming at applications as a projectile-borne video reconnaissance system, the overall design and prototype in principle of a mortar video reconnaissance system bomb were developed. Mortar launched test results show that the initial integrated system was capable of transmitting images through tens of kilometers with the image resolution identifying effectively tactical targets such as roads, hills, caverns, trees and rivers. The projectile-borne video reconnaissance system is able to meet the needs of tactical target identification and battle dage assessment for tactical operations. The study will provide significant technological support for further independent development.

  20. Penetration of rod projectiles in semi-infinite targets : a validation test for Eulerian X-FEM in ALEGRA.

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung Yoon; Leavy, Richard Brian [U.S. Army Research Laboratory, Aberdeen Proving Grounds, MD; Niederhaus, John Henry J.

    2013-03-01

    The finite-element shock hydrodynamics code ALEGRA has recently been upgraded to include an X-FEM implementation in 2D for simulating impact, sliding, and release between materials in the Eulerian frame. For validation testing purposes, the problem of long-rod penetration in semi-infinite targets is considered in this report, at velocities of 500 to 3000 m/s. We describe testing simulations done using ALEGRA with and without the X-FEM capability, in order to verify its adequacy by showing X-FEM recovers the good results found with the standard ALEGRA formulation. The X-FEM results for depth of penetration differ from previously measured experimental data by less than 2%, and from the standard formulation results by less than 1%. They converge monotonically under mesh refinement at first order. Sensitivities to domain size and rear boundary condition are investigated and shown to be small. Aside from some simulation stability issues, X-FEM is found to produce good results for this classical impact and penetration problem.

  1. Measurement of Spin of Projectiles

    Directory of Open Access Journals (Sweden)

    S. R. Verma

    1989-01-01

    Full Text Available Hitherto the spin of the projectile has been measured with the help of spin loop method (for magnetised projectiles and Multishot Ballistic Synchro method (for magnetised and non-magnetised projectiles. This paper discusses the method of measurement of spinwith a single ballistic synchro picture; the advantage of this method is that it dispenses with elaborate and precise optical alignment, required for Multishot Ballistic Synchro method.

  2. Experimental and numerical study on fragmentation of steel projectiles

    Directory of Open Access Journals (Sweden)

    Hopperstad O.S.

    2012-08-01

    Full Text Available A previous experimental study on penetration and perforation of circular Weldox 460E target plates with varying thicknesses struck by blunt-nose projectiles revealed that fragmentation of the projectile occurred if the target thickness or impact velocity exceeded a certain value. Thus, numerical simulations that do not account for fragmentation during impact can underestimate the perforation resistance of protective structures. Previous numerical studies have focused primarily on the target plate behaviour. This study considers the behaviour of the projectile and its possible fragmentation during impact. Hardened steel projectiles were launched at varying velocities in a series of Taylor tests. The impact events were captured using a high-speed camera. Fractography of the fragmented projectiles showed that there are several fracture mechanisms present during the fragmentation process. Tensile tests of the projectile material revealed that the hardened material has considerable variations in yield stress and fracture stress and strain. In the finite element model, the stress-strain behaviour from tensile tests was used to model the projectile material with solid elements and the modified Johnson-Cook constitutive relation. Numerical simulations incorporating the variations in material properties are capable of reproducing the experimental fracture patterns, albeit the predicted fragmentation velocities are too low.

  3. Experimental and numerical study on fragmentation of steel projectiles

    Science.gov (United States)

    Råkvaag, K. G.; Børvik, T.; Hopperstad, O. S.; Westermann, I.

    2012-08-01

    A previous experimental study on penetration and perforation of circular Weldox 460E target plates with varying thicknesses struck by blunt-nose projectiles revealed that fragmentation of the projectile occurred if the target thickness or impact velocity exceeded a certain value. Thus, numerical simulations that do not account for fragmentation during impact can underestimate the perforation resistance of protective structures. Previous numerical studies have focused primarily on the target plate behaviour. This study considers the behaviour of the projectile and its possible fragmentation during impact. Hardened steel projectiles were launched at varying velocities in a series of Taylor tests. The impact events were captured using a high-speed camera. Fractography of the fragmented projectiles showed that there are several fracture mechanisms present during the fragmentation process. Tensile tests of the projectile material revealed that the hardened material has considerable variations in yield stress and fracture stress and strain. In the finite element model, the stress-strain behaviour from tensile tests was used to model the projectile material with solid elements and the modified Johnson-Cook constitutive relation. Numerical simulations incorporating the variations in material properties are capable of reproducing the experimental fracture patterns, albeit the predicted fragmentation velocities are too low.

  4. Comparison of less lethal 40 mm sponge projectile and the 37 mm projectile for injury assessment on human thorax

    Directory of Open Access Journals (Sweden)

    Oukara A.

    2012-08-01

    Full Text Available Since there is an increasing interest in avoiding human body injury in diverse situations like crowd control or peacekeeping missions, less lethal ammunition are more and more used. In this study we focus only on kinetic energy non-lethal (KENLW projectiles. Their desired effects on human body are the temporary incapacitation through blunt trauma. There are different types of KENLW projectiles ranging from rigid to deformable projectiles. Unfortunately, the effects of such projectiles are not really well known as it is difficult to measure the force transmitted to the human body or the related deformation. Because the potential of injury excludes human living tests, tests are performed on cadavers, animals or human tissue surrogates. Besides these tests, numerical simulations are more and more used to gain more understanding, to assess or to predict the effects of this kind of projectile on human body. In this paper a comparison based on the viscous criterion between the 37 mm rigid projectile and the 40 mm sponge projectile was made.

  5. 一维增程修正弹地面密集度的试验方法%Test Method for Dispersion of Extended Range for One-dimensional Trajectory Correction Projectile

    Institute of Scientific and Technical Information of China (English)

    舒延春

    2014-01-01

    一维增程修正弹的地面密集度是评价修正效果的重要战技指标,其试验方法与常规弹药射击密集度试验明显不同。依据一维增程修正弹的修正原则,利用落点散布的正态分布特性与双侧100a百分位点,确定密集度试验边界最低可接受值以及最佳“调节裕量”,并通过仿真计算得到最佳“调节裕量”随密集度的变化规律,为靶场进行一维增程修正弹密集度试验提供一定的借鉴。%It’s an important tactical and technical index of the ground artillery dispersion of extended range for one-dimensional trajectory correction projectile to evaluate its correction effect,and the test meth-od is different comparatively to the conventional artillery’s.Utilizing the characteristic of the ground atille-ry dispersion of normal distribution and double-sided 100a reference interval,the minimum acceptable bound value for the ground artillery dispersion test and the optimization regulated margin are ascertained by the correction principle of the one-dimensional trajectory correction projectile.At the same time,the best regulated margin of the changing law can be gained by the simulation on the different firing ground disper-sion.The results can provide references for One-dimensional Trajectory Correction Projectile on the firing consistency on the range test.

  6. Injury Risk Assessment of Non-Lethal Projectile Head Impacts

    OpenAIRE

    Oukara, Amar; Nsiampa, Nestor; Robbe, Cyril; Papy, Alexandre

    2014-01-01

    Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports ...

  7. Fragmentation of hypervelocity aluminum projectiles on fabrics

    Science.gov (United States)

    Rudolph, Martin; Schäfer, Frank; Destefanis, Roberto; Faraud, Moreno; Lambert, Michel

    2012-07-01

    This paper presents work performed for a study investigating the ability of different flexible materials to induce fragmentation of a hypervelocity projectile. Samples were chosen to represent a wide range of industrially available types of flexible materials like ceramic, aramid and carbon fabrics as well as a thin metallic mesh. Impact conditions and areal density were kept constant for all targets. Betacloth and multi-layer insulation (B-MLI) are mounted onto the targets to account for thermal system engineering requirements. All tests were performed using the Space light-gas gun facility (SLGG) of the Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI. Projectiles were aluminum spheres with 5 mm diameter impacting at approximately 6.3 km/s. Fragmentation was evaluated using a witness plate behind the target. An aramid and a ceramic fabric lead the ranking of fabrics with the best projectile fragmentation and debris cloud dispersion performance. A comparison with an equal-density rigid aluminum plate is presented. The work presented can be applied to optimize the micrometeoroid and space debris (MM/SD) shielding structure of inflatable modules.

  8. Strain Measurement for Hollow Projectiles During Its Penetration of Concrete Targets

    Institute of Scientific and Technical Information of China (English)

    王琳; 王富耻; 王鲁; 李树奎

    2004-01-01

    Gives a new technique to measure the dynic deformation behavior and strain development of a hollow steel projectile during its penetration of concrete targets. Direct strain measurement was performed by applying strain gages attached to the inner walls of the hollow projectile, linked with on-board testing and storage recorder. This on-board test-record system is easy to operate, cost-effective and can provide reasonable, accurate and detailed information. Obverse ballistic experiments were carried out on ogival-nose hollow projectiles normally impacting concrete targets at velocities from 150 m/s to 300 m/s. The deformation process of projectiles was measured, recorded and played back. Profiles of voltage-time relationship were successively obtained and transfered to strain-time relationship with the aid of calibration tables. It was found that projectiles go through a series of compression and tension deformations intermittently. Relationships between strain development and projectile deformation process were discussed.

  9. Projectile penetration into ballistic gelatin.

    Science.gov (United States)

    Swain, M V; Kieser, D C; Shah, S; Kieser, J A

    2014-01-01

    Ballistic gelatin is frequently used as a model for soft biological tissues that experience projectile impact. In this paper we investigate the response of a number of gelatin materials to the penetration of spherical steel projectiles (7 to 11mm diameter) with a range of lower impacting velocities (number of predictive relationships available in the literature, it is found that over the range of projectiles and compositions used, the results fit a simple relationship that takes into account the projectile diameter, the threshold velocity for penetration into the gelatin and a value of the shear modulus of the gelatin estimated from the threshold velocity for penetration. The normalised depth is found to fit the elastic Froude number when this is modified to allow for a threshold impact velocity. The normalised penetration data are found to best fit this modified elastic Froude number with a slope of 1/2 instead of 1/3 as suggested by Akers and Belmonte (2006). Possible explanations for this difference are discussed. PMID:24184862

  10. Injury risk assessment of non-lethal projectile head impacts.

    Science.gov (United States)

    Oukara, Amar; Nsiampa, Nestor; Robbe, Cyril; Papy, Alexandre

    2014-01-01

    Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports may not be appropriate. Therefore, there is a need of a specific approach to assess the lethality of these projectiles. In this framework, some recent research data referred in this article as "force wall approach" suggest the use of three lesional thresholds (unconsciousness, meningeal damages and bone damages) that depend on the intracranial pressure. Three corresponding critical impact forces are determined for a reference projectile. Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile. In order to validate the consistence of this innovative method, it is necessary to compare the results with other existing assessment methods. This paper proposes a comparison between the "force wall approach" and two different head models. The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics. PMID:25400712

  11. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    CERN Document Server

    Wee, Loo Kang; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This paper reports the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When computer model building learning processes is supported and driven by video analysis data, this free Open Source Physics (OSP) tool can provide opportunities for students to engage in active inquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions of projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modeling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  12. Using Tracker as a pedagogical tool for understanding projectile motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Hwee Goh, Giam; Tan, Samuel; Lee, Tat Leong

    2012-07-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions concerning projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real-life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modelling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  13. Projectiles, pendula, and special relativity

    CERN Document Server

    Price, R H

    2005-01-01

    The kind of flat-earth gravity used in introductory physics appears in an accelerated reference system in special relativity. From this viewpoint, we work out the special relativistic description of a ballistic projectile and a simple pendulum, two examples of simple motion driven by earth-surface gravity. The analysis uses only the basic mathematical tools of special relativity typical of a first-year university course.

  14. Dispersion Analysis of the XM881APFSDS Projectile

    Directory of Open Access Journals (Sweden)

    Thomas F. Erline

    2001-01-01

    Full Text Available This study compares the results of a dispersion test with mathematical modeling. A 10-round group of modified 25-mm XM881 Armor Piercing Fin Stabilized Discarding Sabot projectiles was fired from the M242 chain gun into a designated target. The mathematical modeling results come from BALANS, a product of Arrow Tech Associates. BALANS is a finite-element lumped parameter code that has the capability to model a flexible projectile being fired from a flexible gun. It also has the unique feature of an automated statistical evaluation of dispersion. This study represents an effort to evaluate a simulation approach with experiment.

  15. Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

    Science.gov (United States)

    Wu, Hao; Fang, Qin; Zhang, Ya-Dong; Gong, Zi-Ming

    2012-12-01

    Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic performances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetration (DOP), perforation limit thickness, ballistic limit velocity, residual velocity and perforation ratio, with the projectile nosed geometries and projectile-target interfacial friction taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the results of the proposed formulae and existing empirical formulae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/(π S). The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1-3.5 for concrete targets.

  16. Semi-theoretical analyses of the concrete plate perforated by a rigid projectile

    Institute of Scientific and Technical Information of China (English)

    Hao Wu; Qin Fang; Ya-Dong Zhang; Zi-Ming Gong

    2012-01-01

    Based on the three-stage perforation model,a semi-theoretical analysis is conducted for the ballistic performances of a rigid kinetic projectile impacting on concrete plates.By introducing the projectile resistance coefficients,dimensionless formulae are proposed for depth of penetration (DOP),perforation limit thickness,ballistic limit velocity,residual velocity and perforation ratio,with the projectile nosed geometries and projectile-target interfacial friction taken into account.Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets,a new expression is obtained for target strength parameter.By comparisons between the results of the proposed formulae and existing empirical formulae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets,the validations of the proposed formulae are verified.It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters.The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/(πS).The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity.The variation range of the perforation ratio is 1-3.5 for concrete targets.

  17. Projectile Balloting Attributable to Gun Tube Curvature

    Directory of Open Access Journals (Sweden)

    Michael M. Chen

    2010-01-01

    Full Text Available Transverse motion of a projectile during launch is detrimental to firing accuracy, structural integrity, and/or on-board electronics performance of the projectile. One manifest contributing factor to the undesired motion is imperfect bore centerline straightness. This paper starts with the presentation of a deterministic barrel model that possesses both vertical and lateral deviations from centerline in accordance with measurement data, followed by a novel approach to simulating comprehensive barrel centerline variations for the investigation of projectile balloting^1 motions. A modern projectile was adopted for this study. In-bore projectile responses at various locations of the projectile while traveling through the simulated gun tubes were obtained. The balloting was evaluated in both time and frequency domains. Some statistical quantities and the significance were outlined.

  18. Mathematical Model to Simulate the Trajectory Elements ofan Artillery Projectile Proof Shot

    Directory of Open Access Journals (Sweden)

    K.K. Chand

    2007-01-01

    Full Text Available In external ballistics of a conventional spin-stabilised artillery projectile, there are a numberof trajectory models developed for computing trajectory elements having varying degrees ofcomplexity. The present study attempts to propose a single mathematical model, viz., simplifiedpoint-mass/simple particle trajectory model to simulate the trajectory elements of a typical spin-stabilised flat-head artillery projectile proof shot. Due to difficulties in the projectile shape andsize, and the complicated nature of air resistance, an accurate mathematical prediction of thetrajectory is difficult. To simplify the computations, the governing equations of motion of theprojectile have been simplified and assumed that the projectile is a particle and the only forcesacting on the projectile are drag and gravity. With this model, trajectory elements have beengenerated and compared with experimental results obtained in the field test. The measuringinstrument used in this case is a Doppler radar.

  19. Projectile development for railguns using hypervelocity preacceleration

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. [Lawrence Livermore National Lab., CA (United States); Sauve, G.L. [EG and G Rocky Flats, Inc., Golden, CO (United States); Konrad, C.H. [Sandia National Labs., Albuquerque, NM (United States); Hickman, R.J. [Ktech Corp., Albuquerque, NM (United States)

    1991-02-01

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experience at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  20. Projectile development for railguns using hypervelocity preacceleration

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. (Lawrence Livermore National Lab., CA (United States)); Ang, J.A.; Asay, J.R.; Hall, C.A.; Konrad, C.H. (Sandia National Labs., Albuquerque, NM (United States)); Sauve, G.L. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant); Hickman, R.J. (Ktech Corp., Albuquerque, NM (United States))

    1992-03-20

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experiment at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  1. Projectile development for railguns using hypervelocity preacceleration

    Science.gov (United States)

    Susoeff, A. R.; Hawke, R. S.; Ang, J. A.; Asay, J. R.; Hall, C. A.; Konrad, C. H.; Sauve, G. L.

    1992-03-01

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experimentation at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  2. Reliability estimates for flawed mortar projectile bodies

    Energy Technology Data Exchange (ETDEWEB)

    Cordes, J.A. [US Army ARDEC, AMSRD-AAR-MEF-E, Analysis and Evaluation Division, Fuze and Precision Armaments Technology Directorate, US Army Armament Research Development and Engineering Center, Picatinny Arsenal, NJ 07806-5000 (United States)], E-mail: jennifer.cordes@us.army.mil; Thomas, J.; Wong, R.S.; Carlucci, D. [US Army ARDEC, AMSRD-AAR-MEF-E, Analysis and Evaluation Division, Fuze and Precision Armaments Technology Directorate, US Army Armament Research Development and Engineering Center, Picatinny Arsenal, NJ 07806-5000 (United States)

    2009-12-15

    The Army routinely screens mortar projectiles for defects in safety-critical parts. In 2003, several lots of mortar projectiles had a relatively high defect rate, 0.24%. Before releasing the projectiles, the Army reevaluated the chance of a safety-critical failure. Limit state functions and Monte Carlo simulations were used to estimate reliability. Measured distributions of wall thickness, defect rate, material strength, and applied loads were used with calculated stresses to estimate the probability of failure. The results predicted less than one failure in one million firings. As of 2008, the mortar projectiles have been used without any safety-critical incident.

  3. Scale effect of spherical projectiles for stabilization of oblique detonation waves

    Science.gov (United States)

    Maeda, S.; Sumiya, S.; Kasahara, J.; Matsuo, A.

    2015-03-01

    Oblique detonation waves (ODWs) were stabilized by launching a spherical projectile with 1.2-1.4 times the Chapman-Jouguet (C-J) velocity into detonable mixtures at rest. We used smaller projectiles (3.18 mm diameter) than those (4.76 mm diameter) in our previous studies and investigated the effect of the projectile scale on the stabilization of ODWs. We carried out high time resolution schlieren visualization using a high-speed camera. The detonable mixtures used were stoichiometric oxygen mixtures with acetylene, ethylene or hydrogen. They were diluted with argon with a 50 % volumetric fraction, and a dilute mixture containing 75 % argon was also tested for the acetylene/oxygen mixture. Here, we discuss the detonation stability in terms of the curvature effect arising from the three-dimensional nature of a stabilized ODW around a projectile. The curvature effect attenuated the detonation wave to below its C-J velocity in the vicinity of the projectile before the wave velocity asymptotically reached the C-J velocity in the far field. Our previous study showed that the propagation limit of the curvature effect is responsible for the stabilizing criticality of detonation waves. By obtaining detailed distributions of the wave propagation velocity and radius of curvature at the stabilizing criticality, we showed that the radius of curvature at the local minimum point of the wave propagation velocity represents the critical radius of curvature required for curved self-sustained detonation. In this study, we focused on this critical mode of the stabilized ODW for a small projectile (3.18 mm diameter). Distributions of the wave velocity and radius of curvature were obtained in the critical mode of the stabilized ODW. We compare these distributions with those for a larger projectile (4.76 mm diameter) and discuss the stabilizing criticality. For the small projectile, the observed combustion regimes had qualitatively the same trend for the initial pressure of the mixture

  4. Projectile attitude and position determination using magnetometer sensor only

    Science.gov (United States)

    Changey, Sebastien; Fleck, Volker; Beauvois, Dominique

    2005-03-01

    A priori information given by the complete modelling of the ballistic behavior (trajectory, attitude) of the projectile is simplified to give a pertinent reduced evolution model. An algorithm based on extended Kalman filters is designed to determinate: " position: x,y,z references in earth frame. " value and direction of the velocity vector; its direction is given by 2 angles (η and θ). " attitude around velocity vector given by 3 angles: roll angle in the range [0, 2π], angle of attack α and side-slip angle β in the range of few milliradians. The estimation is based on the measures of the magnetic field of the earth given by a three-axis magnetometer sensor embedded on the projectile. The algorithm also needs the knowledge of the direction of the earth magnetic fields in the earth frame and aerodynamics coefficients of the projectile. The algorithm has been tested on simulation, using real evolution of attitude data for a shot with a 155 mm rotating projectile over a distance of 16 km, with wind and measurement noise. The results show that we can estimate milliradians with non-linear equations and approximations, with good precision.

  5. Plastic Guidance Fins for Long Rod Projectiles .

    Directory of Open Access Journals (Sweden)

    Mark L. Bundy

    1997-10-01

    Full Text Available Projectile tail fins on long rod kinetic energy (KE penetrators serve the same purpose as fletchings (feathers on an arrow, namely, they help align the projectile axis with its velocity vector. This reduces the projectile's yaw and hence reduces its aerodynamic drag. In addition, a low yaw angle at target impact helps to maximise the projectile's target penetration. It is typical for projectiles to exit the gun muzzle and enter free flight at some ndn-zero yaw angle. Aerodynamic forces acting on yawed tail fins create a stabilising torque about the projectile's centre of gravity (CG. This torque can be increased by making the fin material lighter. Most conventional long rod penetrators fired from high performance guns have tail fins made from aluminium. However, aluminium can undergo catastrophic oxidation (rapid burning in-bore. Coating aluminium with Al/sub 2/O/sub 3/ {hardcoat prevents ignition of the substrate, provided solid propellant grain impacts do not chip the brittle hardcoat off the surface. Plastic is lighter than aluminium and less exothermic when oxidized. Therefore, other factors aside, it is conceivable that plastic fins could increase projectile stability while incurring less thermal erosion than aluminium. However, thermal loads are not the only concern when considering plastic as an alternative tail fin material. The mechanical strength of plastic is also a critical factor. This paper discusses some of the successes and failures of plastic fins, at least relatively thin fins, for use as KE stabilisers.

  6. Non-invasive timing of gas gun projectiles with light detection and ranging

    International Nuclear Information System (INIS)

    We have developed a Light Detection and Ranging (LIDAR) diagnostic to track the position of a projectile inside of a gas gun launch tube in real-time. This capability permits the generation of precisely timed trigger pulses useful for triggering high-latency diagnostics such as a flash lamp-pumped laser. An initial feasibility test was performed using a 72 mm bore diameter single-stage gas gun routinely used for dynamic research at Los Alamos. A 655 nm pulsed diode laser operating at a pulse repetition rate of 100 kHz was used to interrogate the position of the moving projectile in real-time. The position of the projectile in the gun barrel was tracked over a distance of ∼ 3 meters prior to impact. The position record showed that the projectile moved at a velocity of 489 m/s prior to impacting the target. This velocity was in good agreement with independent measurements of the projectile velocity by photon Doppler velocimetry and timing of the passage of the projectile through optical marker beams positioned at the muzzle of the gun. The time-to-amplitude conversion electronics used enable the LIDAR data to be processed in real-time to generate trigger pulses at preset separations between the projectile and target.

  7. Stability Criterion for a Finned Spinning Projectile

    Directory of Open Access Journals (Sweden)

    S. D. Naik

    2000-01-01

    Full Text Available The state-of-the-art in gun projectile technology has been used for the aerodynamic stabilisation.This approach is acceptable for guided and controlled rockets but the free-flight rockets suffer fromunacceptable dispersion. Sabot projectiles with both spin and fms developed during the last decadeneed careful analysis. In this study, the second method of Liapunov has been used to develop stability criterion for a projectile to be designed with small fins and is made to spin in the flight. This criterion is useful for the designer.

  8. A novel apoptosis correlated molecule: expression and characterization of protein Latcripin-1 from Lentinula edodes C(91-3).

    Science.gov (United States)

    Liu, Ben; Zhong, Mintao; Lun, Yongzhi; Wang, Xiaoli; Sun, Wenchang; Li, Xingyun; Ning, Anhong; Cao, Jing; Zhang, Wei; Liu, Lei; Huang, Min

    2012-01-01

    An apoptosis correlated molecule-protein Latcripin-1 of Lentinula edodes C(91-3)-was expressed and characterized in Pichia pastoris GS115. The total RNA was obtained from Lentinula edodes C(91-3). According to the transcriptome, the full-length gene of Latcripin-1 was isolated with 3'-Full Rapid Amplification of cDNA Ends (RACE) and 5'-Full RACE methods. The full-length gene was inserted into the secretory expression vector pPIC9K. The protein Latcripin-1 was expressed in Pichia pastoris GS115 and analyzed by Sodium Dodecylsulfonate Polyacrylate Gel Electrophoresis (SDS-PAGE) and Western blot. The Western blot showed that the protein was expressed successfully. The biological function of protein Latcripin-1 on A549 cells was studied with flow cytometry and the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl-tetrazolium Bromide (MTT) method. The toxic effect of protein Latcripin-1 was detected with the MTT method by co-culturing the characterized protein with chick embryo fibroblasts. The MTT assay results showed that there was a great difference between protein Latcripin-1 groups and the control group (p < 0.05). There was no toxic effect of the characterized protein on chick embryo fibroblasts. The flow cytometry showed that there was a significant difference between the protein groups of interest and the control group according to apoptosis function (p < 0.05). At the same time, cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. The work demonstrates that protein Latcripin-1 can induce apoptosis of human lung cancer cells A549 and brings new insights into and advantages to finding anti-tumor proteins. PMID:22754362

  9. AN EXPERIMENTAL TECHNIQUE TO MEASURE PROJECTILE DECELERATION HISTORY DURING NORMAL PENETRATION

    Institute of Scientific and Technical Information of China (English)

    INTO PLAIN; Liu Xiaohu; Liu Ji; Wang Cheng

    2000-01-01

    The present paper presents a new experimental method to measure the deceleration time his tory of projectiles penetrating into concrete in full-size test. The experiment can be carried out by using an onboard accelerometer to measure the projectile deceleration history and the data are transmitted to a ground recording system. With this experimental method, a series of tests on hemisphere-nose steel projectiles pene trating normally into plain concrete at the velocity region 150 - 400 m/s have been executed and the deceler ation histories obtained. The high frequency portion in the deceleration data has been investigated and proved to be the structure response of projectile. The characteristics of deceleration history have also been analyzed and discussed.

  10. Pepper spray projectile/disperser for countering hostage and barricade situations

    Science.gov (United States)

    Kelly, Roy

    1997-01-01

    An improved less-than-lethal projectile for use in hostage, barricade and tactical assault situations has been developed. The projectile is launched from a standoff position and disperse the incapacitating agent oleoresin capsicum in the form of atomized droplets. A literature search followed by an experimental study were conducted of the mechanism of barrier defeat for various shaped projectiles against the targets of interest in this work: window glass, plasterboard and plywood. Some of the trade- offs between velocity, standoff, projectile shape and size, penetration, and residual energy were quantified. Analysis of the ballistic trajectory and recoil, together with calculations of he amount of pepper spray needed to incapacitate the occupants of a typical barricaded structure, indicated the suitability of using a fin stabilized projectile fired from a conventional 37 mm riot control gas gun. Two projectile designs were considered, manufactured and tested. The results of static tests to simulate target impact, together with live firing trials against a variety of targets, showed that rear ejection of the atomized spray was more reproducible and effective than nose ejection. The performance characteristics of the finalized design were investigated in trials using the standard barrier for testing barrier penetrating tear gas agents as defined by the National Institute of Justice.

  11. Acceleration Measurement of Projectile High Velocity Penetrating Concrete Target and Acceleration Signal Analysis

    Institute of Scientific and Technical Information of China (English)

    Peng XU; Jing ZU; Jing-biao FAN

    2010-01-01

    A kind of novel on-boand memory acceleratian measure equipment, self-developed, had been employed in recent field test to obtain the acceleration of projectile penetrating many kinds of concrete target. At the same time, the aluminum foam with different density and pore-diameters had been utilized to protect cirruit modules. Fur-thermore, with the theoretical analysis, computer simulation and field test, the high frequency's impact on the tested acceleration of the projectile had been discussed; At last, the analysis on output signal tested the validity of test data.

  12. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system.

    Science.gov (United States)

    Suravajhala, Prashanth; Kogelman, Lisette J A; Mazzoni, Gianluca; Kadarmideen, Haja N

    2015-01-01

    With unprecedented increase in next generation sequencing technologies, there has been a persistent interest on transcript profiles of long non-coding RNAs (lncRNAs) and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI), gene network models such as Weighted Gene Co-expression Network Analysis (WGCNA) are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases. PMID:26284111

  13. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system

    Directory of Open Access Journals (Sweden)

    Prashanth eSuravajhala

    2015-07-01

    Full Text Available With unprecedented increase in next generation sequencing (NGS technologies, there has been a persistent interest on transcript profiles of long noncoding RNAs (lncRNAs and protein-coding genes forming an interaction network. Apart from protein-protein interaction (PPI, gene network models such as Weighted Gene Co-expression Network Analysis are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing transcript structures and understanding expression profiles mediating regulatory roles. In the current exploratory analysis, we show how a lncRNA - cyp2c91 contributes to the transcriptional regulation localized to cytoplasm thereby making refractory environment for transcription. By applying network methods and pathway analyses on genes related to a disease such as obesity and systemic lupus erythematosus, we show that we can gain deeper insight in biological processes such as the perturbances in immune system, and get a better understanding of the systems biology of diseases.

  14. Three Dimensional CAPP Technology of Projectile Based on MBD

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhao

    2013-07-01

    Full Text Available This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of three-dimensional computer-assisted process design technology of projectile based on model definition can shorten the design cycle of projectile, thus improving rapid manufacturing capacity of product and reducing cost.

  15. Penetration Experiments with 6061-T6511 Aluminum Targets and Spherical-Nose Steel Projectiles at Striking Velocities Between 0.5 and 3.0 km/s

    Energy Technology Data Exchange (ETDEWEB)

    Forrestal, M.J.; Piekutowski, A.J.

    1999-02-04

    We conducted depth of penetration experiments with 7.11-mm-diameter, 74.7-mm-long, spherical-nose, 4340 steel projectiles launched into 250-mm-diameter, 6061-T6511 aluminum targets. To show the effect of projectile strength, we used projectiles that had average Rockwell harnesses of R{sub c} = 36.6, 39.5, and 46.2. A powder gun and two-stage, light-gas guns launched the 0.023 kg projectiles at striking velocities between 0.5 and 3.0 km/s. Post-test radiographs of the targets showed three response regions as striking velocities increased: (1) the projectiles remained visibly undeformed, (2) the projectiles permanently deformed without erosion, and (3) the projectiles eroded and lost mass. To show the effect of projectile strength, we compared depth-of-penetration data as a function of striking velocity for spherical-nose rods with three Rockwell harnesses at striking velocities ranging from 0.5 to 3.0 km/s. To show the effect of nose shape, we compared penetration data for the spherical-nose projectiles with previously published data for ogive-nose projectiles.

  16. Fatal lawn mower related projectile injury

    DEFF Research Database (Denmark)

    Colville-Ebeling, Bonnie; Lynnerup, Niels; Banner, Jytte

    2014-01-01

    Fatal lawn mower related injuries are a relatively rare occurrence. In a forensic setting, the primary aim is to reconstruct the injury mechanism and establish the cause of death. A relatively rare, but characteristic type of injury is a so-called projectile or missile injury. This occurs when...... the operator or a bystander is impacted by an object mobilized from the grass by the rotating mower blades. This type of injury often leaves only modest external trauma, which increases the risk of overlooking an entry wound. In this paper we present a case of a fatal lawn mower related projectile injury which...... was initially overlooked, later interpreted as a possible gunshot homicide, and finally identified as a lawn mower related projectile injury when autopsy revealed a piece of metal thread in the main bronchus to the right middle lobe, hemopericardium, and right-sided hemothorax. To our knowledge, this injury...

  17. Isoscaling of projectile-like fragments

    Institute of Scientific and Technical Information of China (English)

    Zhong Chen; Chen Jin-Hui; Guo Wei; Ma Chun-Wang; Ma Guo-Liang; Su Qian-Min; Yan Ting-Zhi; Zuo Jia-Xu; Ma Yu-Gang; Fang De-Qing; Cai Xiang-Zhou; Chen Jin-Gen; Shen Wen-Qing; Tian Wen-Dong; Wang Kun; Wei Yi-Bin

    2006-01-01

    In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragments has been discussed. The isoscaling parameters α andβ have been extracted respectively, for hot fragments before evaporation and cold fragments after evaporation. It looks that the evaporation has stronger effect on α than β. For cold fragments,a monotonic increase of α and |β| with the increase of Z and N is observed. The relation between isoscaling parameter and the change of isospin content is discussed.

  18. Three Dimensional CAPP Technology of Projectile Based on MBD

    OpenAIRE

    Hongzhi Zhao; Yingai Piao; Xiaoyong Zhu

    2013-01-01

    This study aims at the research goal of three-dimensional digital process design of projectile, which adopts three-dimensional computer-aided process design technology based on MBD and uses MBD to conduct parametric modeling of projectile that can reduce the input of projectile’s process information and data conversion and produce reasonable, feasible and three-dimensional projectile manufacturing process to realize paperless three-dimensional process design of projectile. The application of ...

  19. Speed, Acceleration, Chameleons and Cherry Pit Projectiles

    Science.gov (United States)

    Planinsic, Gorazd; Likar, Andrej

    2012-01-01

    The paper describes the mechanics of cherry pit projectiles and ends with showing the similarity between cherry pit launching and chameleon tongue projecting mechanisms. The whole story is written as an investigation, following steps that resemble those typically taken by scientists and can therefore serve as an illustration of scientific…

  20. Launching a Projectile into Deep Space

    Science.gov (United States)

    Maruszewski, Richard F., Jr.

    2004-01-01

    As part of the discussion about Newton's work in a history of mathematics course, one of the presentations calculated the amount of energy necessary to send a projectile into deep space. Afterwards, the students asked for a recalculation with two changes: First the launch under study consisted of a single stage, but the students desired to…

  1. A note on stability of motion of a projectile

    Indian Academy of Sciences (India)

    S D Naik

    2001-08-01

    A projectile is stabilised using either gyroscopic or aerodynamic stability. But subcalibre projectiles with sabot have both spin and fins. Separate stability criteria are researched generally for each type of projectile. In this paper a stability criterion which can be used for all such bodies has been developed through the Liapunov second method.

  2. Initiation of Gaseous Detonation by Conical Projectiles

    Science.gov (United States)

    Verreault, Jimmy

    Initiation and stabilization of detonation by hypersonic conical projectiles launched into combustible gas mixtures is investigated. This phenomenon must be understood for the design and optimization of specific hypersonic propulsion devices, such as the oblique detonation wave engine and the ram accelerator. The criteria for detonation initiation by a projectile is also related to fundamental aspects of detonation research, such as the requirement for direct initiation of a detonation by a blast wave. Experimental results of this problem also offer useful references for validation of numerical and theoretical modeling. Projectiles with cone half angles varying from 15° to 60° were launched into stoichiometric mixtures of hydrogen/oxygen with 70% argon dilution at initial pressures between 10 and 200 kPa. The projectiles were launched from a combustion-driven gas gun at velocities up to 2.2 km/s (corresponding to 133% of the Chapman Jouguet velocity). Pictures of the flowfields generated by the projectiles were taken via Schlieren photography. Five combustion regimes were observed about the projectile ranging from prompt and delayed oblique detonation wave formation, combustion instabilities, a wave splitting, and an inert shock wave. Two types of transition from the prompt oblique detonation wave regime to the inert shock regime were observed. The first (the delayed oblique detonation wave regime) showed an inert shock attached to the tip of the projectile followed by a sharp kink at the onset of an oblique detonation wave; this regime occurred by decreasing the cone angle at high mixture pressures. The second (the combustion instabilities regime) exhibited large density gradients due to combustion ignition and quenching phenomena; this regime occurred by decreasing the mixture pressure at large cone angles. A number of theoretical models were considered to predict critical conditions for the initiation of oblique detonations. The Lee-Vasiljev model agreed

  3. Aerodynamic Characteristics of Projectile with Exotic Wraparound Wings Configuration

    Institute of Scientific and Technical Information of China (English)

    Fu Zhang; WenJun Ruan; Hao Wang; ChenGuang Zhu; MengHua Zhang

    2014-01-01

    A projectile with exotic wraparound wings ( WAW ) configuration is designed to improve the fin-stabilized projectile shooting quality. Two fin-stabilized projectiles with the same body with and without exotic WAW configuration are simulated numerically by applying the Roe scheme. The shear-stress transport turbulence models and the lower-upper symmetric Gauss-Seidel implicit method are used to solve 3D Reynolds-averaged Navier-Stokes equations. The differences in aerodynamic coefficients and aerodynamic characteristics of the projectiles when the Mach number varies from 0�35 to 0�95 are obtained, and the cause of these differences is analyzed. The calculation results indicate that the lift-to-drag ratio of the projectile significantly increases, the rolling moment decreases, and the position of the pressure center of the projectile shows relatively small changes when the exotic WAW configuration is used. Therefore, this projectile can obviously reduce rolling effect, enlarge range and improve flying stability.

  4. Investigates on Aerodynamic Characteristics of Projectile with Triangular Cross Section

    Institute of Scientific and Technical Information of China (English)

    YI Wen-jun; WANG Zhong-yuan; LI Yan; QIAN Ji-sheng

    2009-01-01

    The aerodynamic characteristics of projectiles with triangular and circular cross sections are investigated respectively by use of free-flight experiment. Processed the experiment data, curves of flight velocity variation and nutation of both projectiles are obtained, based on the curves, their aerodynamic force and moment coefficients are found out by data fitting, and their aerodynamic performances are compared and analyzed. Results show that the projectile with triangular cross section has smaller resistance, higher lift-drag ratio, better static stability, higher stability capability and more excellent maneuverability than those of the projectile with circular cross section, therefore it can be used in the guided projectiles; under lower rotation speed, the triangular section projectile has greater Magnus moment leading to bigger projectile distribution.

  5. Experimental investigation on underwater trajectory deviation of high-speed projectile with different nose shapes

    Science.gov (United States)

    Zhang, Wei; Huang, Wei; Gao, Yubo; Qi, Yafei; Hypervelocity Impact Research Center Team

    2015-06-01

    Laboratory-scaled oblique water entry experiments for the trajectory stability in the water column have been performed with four different nosed-projectiles at a range of velocities from 20m /s to 250 m /s . The slender projectiles are designed with flat, ogival, hemi-sperical, truncated-ogival noses to make comparisons on the trajectory deviation when they are launched at vertical and oblique impact angles (0°~25°). Two high-speed cameras that are positioned orthogonal to each other and normal to the column are employed to capture the entire process of projectiles' penetration. From the experimental results, the sequential images in two planes are presented to compare the trajectory deviation of different impact tests and the 3D trajectory models are extracted based on the location recorded by cameras. Considering the effect influenced by the impact velocities and noses of projectiles, it merited concluded that trajectory deviation is affected from most by impact angle, and least by impact velocities. Additionally, ogival projectiles tend to be more sensitive to oblique angle and experienced the largest attitude changing. National Natural Science Foundation of China (NO.: 11372088).

  6. Analysis of electrostatic charge on small-arms projectiles

    Science.gov (United States)

    Vinci, Stephen; Zhu, Jack; Hull, David

    2012-06-01

    Triboelectric (frictional) and combustion processes impart electrostatic charge on projectiles as they are fired. Additional charging and discharging processes alter the magnitude of charge in-flight and are complex functions of a plethora of environmental conditions. There is an interest in using electric-field sensors to help detect and track projectiles in counter-sniper and projectile ranging systems. These applications require knowledge of the quantity of charge, as well as the sensitivity of electric-field sensors. The U.S. Army Research Laboratory (ARL) took part in multiple experiments at Aberdeen Proving Grounds (APG) to simulate a battlefield-like environment. Sensors were placed in strategic locations along the bullets' paths and recorded the electric-field signatures of charged small-arms bullets. The focus of this effort was to analyze the electric-field signatures collected during the APG experiment in order to estimate electrostatic charge on the bullets. Algorithms were written to extract electric-field bullet signatures from raw data; these signatures were further processed to estimate the miss distance, velocity and charge. The estimates of range and velocity were compared to similar estimates from acoustic signatures for verification. Ground-truth Global Positioning System (GPS) data were used to independently calculate ranges, azimuths, and miss distances. Signatures were filtered to remove clutter signals from power lines and other unwanted field sources. Closed-form equations were then fitted to the collected signatures to retrieve estimates for the magnitude of charge on the bullets. Test data, collected with sensors placed on a wall, showed enhanced E-field intensity. A Method of Moments (MoM) model of the wall was created to improve signature simulation. Detectable charges on bullets were found to exist in the 1 pC to 1 nC (10-12 - 10-9 C) range. Relationships between estimated charge, gun type, bullet caliber, noise thresholds and number

  7. Minimum and terminal velocities in projectile motion

    CERN Document Server

    Miranda, E N; Riba, R

    2012-01-01

    The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 < Vterm. These results show that the velocity is not a monotonous function. If the initial speed is not horizontal, there is an angle range where the velocity shows the same behavior mentioned previously. Out of that range, the volocity is a monotonous function. These results come out from numerical simulations.

  8. Slit-Drum Camera For Projectile Studies

    Science.gov (United States)

    Liangyi, Chen; Shaoxiang, Zhou; Guanhua, Cha; Yuxi, Hu

    1983-03-01

    The' model XF-70 slit-drum camera has been developed to record projectile in flight for observation and acquisition. It has two operation modes: (1) synchro-ballistic photography, (2) streak record. The film is located on the inner surface of rotating drum to make it travel. The folding mirror is arranged to reflect light beam 90 degree on to film. The assembly of folding mirror and slit aperture can be together rotated about the optical axis of objective so that the camera makes a feature of recording projectile having any launching angle either in synchro-ballistic photography or in streak record through prerotating the folding mirror assembly by an appropriate angle. The mechanical-electric shutter preventing film from reexposing is close to the slit aperture. The loading mechanism is designed for use in daylight. LED fiducial mark and timing mark are printed at the edges of the frame for accurate measurements.

  9. Evaluating simulant materials for understanding cranial backspatter from a ballistic projectile.

    Science.gov (United States)

    Das, Raj; Collins, Alistair; Verma, Anurag; Fernandez, Justin; Taylor, Michael

    2015-05-01

    In cranial wounds resulting from a gunshot, the study of backspatter patterns can provide information about the actual incidents by linking material to surrounding objects. This study investigates the physics of backspatter from a high-speed projectile impact and evaluates a range of simulant materials using impact tests. Next, we evaluate a mesh-free method called smoothed particle hydrodynamics (SPH) to model the splashing mechanism during backspatter. The study has shown that a projectile impact causes fragmentation at the impact site, while transferring momentum to fragmented particles. The particles travel along the path of least resistance, leading to partial material movement in the reverse direction of the projectile motion causing backspatter. Medium-density fiberboard is a better simulant for a human skull than polycarbonate, and lorica leather is a better simulant for a human skin than natural rubber. SPH is an effective numerical method for modeling the high-speed impact fracture and fragmentations. PMID:25739515

  10. The Envelope of Projectile Trajectories in Midair

    CERN Document Server

    Chudinov, P

    2005-01-01

    A classic problem of the motion of a point mass (projectile) thrown at an angle to the horizon is reviewed. The air drag force is taken into account with the drag factor assumed to be constant. Analytic approach is used for investigation. Simple analytical formulas are used for the constructing the envelope of the family of the point mass trajectories. The equation of envelope is applied for determination of maximum range of flight. The motion of a baseball is presented as an example.

  11. Experimental Study and Numerical Simulation of Hypervelocity Projectile Impact on Double-Wall Structure

    Institute of Scientific and Technical Information of China (English)

    陈沿海; 张庆明; 黄风雷

    2004-01-01

    Tests of hypervelocity projectile impact on double-wall structure were performed with the front wall ranging from 0.5 mm to 2.0 mm thick and different impact velocities. Smooth particle hydrodynamics (SPH) code in LS-DYNA was employed for the simulation of hypervelocity impact on the double-wall structure. By using elementary shock wave theory, the experimental results above are analyzed. The analysis can provide an explanation for the penetration mechanism of hypervelocity projectile impact on double-wall structure about the effect of front wall thickness and impact velocity.

  12. Forensic and clinical issues in the use of frangible projectile.

    Science.gov (United States)

    Komenda, Jan; Hejna, Petr; Rydlo, Martin; Novák, Miroslav; Krajsa, Jan; Racek, František; Rejtar, Pavel; Jedlička, Luděk

    2013-08-01

    Frangible projectiles for firearms, which break apart on impact, are mainly used by law enforcement agencies for training purposes, but can also be used for police interventions. Apart from the usual absence of lead in the projectiles, the main advantage of using frangible projectiles is the reduced risk of ricochet after impact with a hard target. This article describes the design and function of frangible projectiles, and describes gunshot wounds caused by ultra-frangible projectiles which fragment after penetration of soft tissues. Shooting experiments performed by the authors confirmed that differences in the geometry and technology of frangible projectiles can significantly modify their wounding effects. Some frangible projectiles have minimal wounding effects because they remain compact after penetration of soft tissues, comparable to standard fully jacketed projectiles. However, a number of ultra-frangible projectiles disintegrate into very small fragments after impact with a soft tissue substitute. In shooting experiments, we found that the terminal behavior of selected ultra-frangible projectiles was similar in a block of ballistic gel and the soft tissues of the hind leg of a pig, except that the degree of disintegration was less in the gel. PMID:23910864

  13. Study on Overall Concept Planning of Terminal Correction Mortar Projectiles

    Institute of Scientific and Technical Information of China (English)

    XU Jin-xiang

    2008-01-01

    The system composition, the operational principle of terminal correction mortar projectiles (TCMP) and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics (CFD) software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.

  14. Hign-speed penetration of projectile with cavitator into sand

    Science.gov (United States)

    Daurskikh, Anna; Veldanov, Vladislav

    2011-06-01

    Cavitators are used in underwater projectiles design to form a cavern in which projectile could move with no or significantly reduced drag. An investigation of possible application of this structural element for penetration into porous media was conducted. High-speed impact of a conical-shaped head projectile with cavitator was studied in terms of its influence on penetration capacity and projectile stability in sand for impact velocity about 1500 m/s. Cavitators were manufactured of steel with different strength moduli, and thus two penetration regimes (with eroding/non-eroding cavitator) were compared. Numerical simulations showing wave propagation in target and projectile were performed in AUTODYN with Johnson-Cook model for projectile and granular model for sand.

  15. Measuring Projectile Velocity using Shock Wave Pressure Sensors

    Directory of Open Access Journals (Sweden)

    Sankarsan Padhy

    2014-11-01

    Full Text Available This paper deals with development of velocity measurement methodology based on projectile shock wave pressure measurements. The measurement principle is based on the fact that, whenever a projectile moves with supersonic velocity, shock wave fronts are produced along the trajectory of the projectile. Measurement configuration has been developed for measuring the shock wave pressure associated with projectile in flight, and hence, projectile velocity has been calculated. This paper covers various aspects of shock waves, generation of N Waves, feasibility study for capturing shock wave using dynamic microphone. Finally, suitable piezo-electric sensor has been selected and deployed in the trials and shock wave signature has been captured. From shock wave pressure, the projectile velocity has been computed.Defence Science Journal, Vol. 64, No. 6, November 2014, pp.499-501, DOI:http://dx.doi.org/10.14429/dsj.64.8108

  16. Penetration of Granular Projectiles into a Water Target

    OpenAIRE

    González-Gutiérrez, Jorge; J. L. Carrillo-Estrada; Ruiz-Suárez, J. C.

    2014-01-01

    The penetration of low-speed projectiles into a water target has been studied in the last several years to understand the physics behind the formation and collapse of cavities. In such studies, the projectiles employed were solid bodies or liquid drops. Here we report similar impact experiments using granular projectiles, with the aim to investigate how the morphology of the cavities is determined by the balance between the dynamic pressure exerted by the fluid and the cohesive strength of th...

  17. Oblique Impact of Projectile on Thin Aluminium Plates

    Directory of Open Access Journals (Sweden)

    W.U. Khan

    2003-04-01

    Full Text Available Experiments were performed, wherein cylindrical projectiles made of hardened steel were impacted on commercially available aluminium plates at different angles. Projectiles were of 12.8 mm diameter and plates were of 0.81 mm, 1.52mm and 1.91mm thicknesses. Based on the experimental results, an analytical model has been developed to predict the residual velocity of the projectile and the ballistic limit of the plate.

  18. Stability analyses of the mass abrasive projectile high-speed penetrating into a concrete target Part III: Terminal ballistic trajectory analyses

    Science.gov (United States)

    Wu, H.; Chen, X. W.; Fang, Q.; Kong, X. Z.; He, L. L.

    2015-08-01

    During the high-speed penetration of projectiles into concrete targets (the impact velocity ranges from 1.0 to 1.5 km/s), important factors such as the incident oblique and attacking angles, as well as the asymmetric abrasions of the projectile nose induced by the target-projectile interactions, may lead to obvious deviation of the terminal ballistic trajectory and reduction of the penetration efficiency. Based on the engineering model for the mass loss and nose-blunting of ogive-nosed projectiles established, by using the Differential Area Force Law (DAFL) method and semi-empirical resistance function, a finite differential approach was programmed (PENTRA2D) for predicting the terminal ballistic trajectory of mass abrasive high-speed projectiles penetrating into concrete targets. It accounts for the free-surface effects on the drag force acting on the projectile, which are attributed to the oblique and attacking angles, as well as the asymmetric nose abrasion of the projectile. Its validation on the prediction of curvilinear trajectories of non-normal high-speed penetrators into concrete targets is verified by comparison with available test data. Relevant parametric influential analyses show that the most influential factor for the stability of terminal ballistic trajectories is the attacking angle, followed by the oblique angle, the discrepancy of asymmetric nose abrasion, and the location of mass center of projectile. The terminal ballistic trajectory deviations are aggravated as the above four parameters increase.

  19. Dynamic analysis of a guided projectile during engraving process

    Directory of Open Access Journals (Sweden)

    Tao Xue

    2014-06-01

    Full Text Available The reliability of the electronic components inside a guided projectile is highly affected by the launch dynamics of guided projectile. The engraving process plays a crucial role on determining the ballistic performance and projectile stability. This paper analyzes the dynamic response of a guided projectile during the engraving process. By considering the projectile center of gravity moving during the engraving process, a dynamics model is established with the coupling of interior ballistic equations. The results detail the stress situation of a guided projectile band during its engraving process. Meanwhile, the axial dynamic response of projectile in the several milliseconds following the engraving process is also researched. To further explore how the different performance of the engraving band can affect the dynamics of guided projectile, this paper focuses on these two aspects: (a the effects caused by the different band geometry; and (b the effects caused by different band materials. The time domain and frequency domain responses show that the dynamics of the projectile are quite sensitive to the engraving band width. A material with a small modulus of elasticity is more stable than one with a high modulus of elasticity.

  20. Projectile development for railguns using hypervelocity preacceleration. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Susoeff, A.R.; Hawke, R.S. [Lawrence Livermore National Lab., CA (United States); Ang, J.A.; Asay, J.R.; Hall, C.A.; Konrad, C.H. [Sandia National Labs., Albuquerque, NM (United States); Sauve, G.L. [EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant; Hickman, R.J. [Ktech Corp., Albuquerque, NM (United States)

    1992-03-20

    The STARFIRE Project is a joint Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) effort to achieve hypervelocity projectile launches up to 15 km/s. The apparatus used to achieve this goal is a three stage acceleration system made up of a two-stage light-gas gun (2SLGG) coupled to a railgun. The 2SLGG is used as a preaccelerator capable of injecting 2 gram projectiles at velocities of 6 km/s or more. Projectiles used in this environment are subject to many conditions. Some of these which effect projectile design include: acceleration loading, structural response, barrel condition and alignment. Development of a projectile to satisfy the programmatic requirements is underway. This report covers the evolution of design and fabrication for railgun projectiles from previous experiment at LLNL to the replenished plasma armature and projectile now used on STARFIRE. Projectile design, development and fabrication methods which use off-the-shelf materials and standard techniques to meet the operational criteria of the experimental program are discussed in this paper. Initial work involving the design and fabrication of skirted projectiles, which are expected to further reduce interaction phenomena between the plasma armature and railgun barrel, is also described.

  1. Dynamic analysis of a guided projectile during engraving process

    Institute of Scientific and Technical Information of China (English)

    Tao XUE; Xiao-bing ZHANG; Dong-hua CUI

    2014-01-01

    The reliability of the electronic components inside a guided projectile is highly affected by the launch dynamics of guided projectile. The engraving process plays a crucial role on determining the ballistic performance and projectile stability. This paper analyzes the dynamic response of a guided projectile during the engraving process. By considering the projectile center of gravity moving during the engraving process, a dynamics model is established with the coupling of interior ballistic equations. The results detail the stress situation of a guided projectile band during its engraving process. Meanwhile, the axial dynamic response of projectile in the several milliseconds following the engraving process is also researched. To further explore how the different performance of the engraving band can affect the dynamics of guided projectile, this paper focuses on these two aspects:(a) the effects caused by the different band geometry;and (b) the effects caused by different band materials. The time domain and frequency domain responses show that the dynamics of the projectile are quite sensitive to the engraving band width. A material with a small modulus of elasticity is more stable than one with a high modulus of elasticity.

  2. New projectiles: multicharged metal clusters and biopolymers

    International Nuclear Information System (INIS)

    Metal clusters and molecules are the one mean to realize simultaneous impacts of several atoms on a reduced surface(∼100A). The interaction characteristics is the non-linearity of energy deposition; the perturbation that the cluster produces, is above than the sum of the perturbation induced by its components, taken separately. The purpose of ORION project is to accelerate these new projectiles at ORSAY Tandem. The considered mass range is from 100 Daltons to 100 000 Daltons and energy range from MeV to GeV

  3. Mass stabilized projectile designs for electromagnetic launch

    International Nuclear Information System (INIS)

    A dual density Rodman cone, with l/d = 7, has been found to be attractive for electromagnetic launch and may have adequate terminal ballistic performance. Stable flight is achieved from the correct distribution of mass within the projectile body. The design provides some flexibility for the armature in that all the armature mass is used for aerodynamic stability. Furthermore, the acceleration can be supported by a simple one-piece armature. A bore rider, which is less than 10% of the total mass, is needed for in-bore stability and structural support at the tungsten/aluminum interface. Work to date has focused on small caliber applications, but substantial gains can be achieved when the bore size is increased to cannon caliber. General design principles are presented for a mass stabilized projectile. This paper addresses nearly all aspects of launch, flight, and terminal effects as a function of bore size. Flight and terminal effects are computed from curve fits to existing experimental data

  4. Penetration of projectiles into granular targets

    Science.gov (United States)

    Ruiz-Suárez, J. C.

    2013-06-01

    Energetic collisions of subatomic particles with fixed or moving targets have been very valuable to penetrate into the mysteries of nature. But the mysteries are quite intriguing when projectiles and targets are macroscopically immense. We know that countless debris wandering in space impacted (and still do) large asteroids, moons and planets; and that millions of craters on their surfaces are traces of such collisions. By classifying and studying the morphology of such craters, geologists and astrophysicists obtain important clues to understand the origin and evolution of the Solar System. This review surveys knowledge about crater phenomena in the planetary science context, avoiding detailed descriptions already found in excellent papers on the subject. Then, it examines the most important results reported in the literature related to impact and penetration phenomena in granular targets obtained by doing simple experiments. The main goal is to discern whether both schools, one that takes into account the right ingredients (planetary bodies and very high energies) but cannot physically reproduce the collisions, and the other that easily carries out the collisions but uses laboratory ingredients (small projectiles and low energies), can arrive at a synergistic intersection point.

  5. Locating the source of projectile fluid droplets

    CERN Document Server

    Varney, Christopher R

    2011-01-01

    The ballistically ill-posed projectile problem of finding source height from spattered droplets of viscous fluid is a longstanding obstacle to accident reconstruction and crime scene analysis. It is widely known how to infer the impact angle of droplets on a surface from the elongation of their impact profiles. Due to missing velocity information, however, finding the height of origin from impact position and angle of individual drops is not possible. Turning to aggregate statistics of the spatter and basic equations of projectile motion familiar to physics students, we introduce a reciprocal correlation plot that is effective when the polar angle of launch is concentrated in a narrow range. The horizontal plot coordinate is twice the reciprocal of impact distance, and the vertical coordinate depends on the orientation of the spattered surface; for a level surface this is the tangent of impact angle. In all cases one infers source height as the slope of data points in the reciprocal correlation plot. Such plo...

  6. Polymer Recovery from Auto Shredder Residue by Projectile Separation Method

    Directory of Open Access Journals (Sweden)

    Dong Yang Wu

    2012-04-01

    Full Text Available The number of vehicles on the road has been increasing at an enormous rate over the last decade. By 2015, the number of vehicles that reach the end of their life will be close to a million per year in Australia. Most metallic parts of the vehicle can be recycled but the plastic components and components of other materials are normally shredded and disposed in landfills. As more vehicles are using composite materials, the percentage of materials sent to landfill is alarming. This paper reviews existing polymer recycling techniques for End-of-Life Vehicles (ELVs and proposes a more efficient electrostatic based projectile separation method. The test rig is at the preliminary stage of development and initial outcomes are promising.

  7. Counter sniper: a small projectile and gunfire localization system

    Science.gov (United States)

    Moore, Fritz; Leslie, Daniel H.; Hyman, Howard; Squire, Mark D.

    2001-02-01

    This paper describes a prototype sensor system for detection and 3D tracking of bullets and other small projectiles. The intended purpose of the system is to rapidly locate a sniper to a few meters accuracy at ranges to 1 km in three dimensions. The system detects and tracks a single bullet, and based on the measured 3D trajectory, backtracks to the sniper location. Details of the system are describe including optics, infrared camera, scanning system, laser ranging system, computer control and electronics, and data reduction algorithm. The system has been field tested against bullets, and has been shown to locate a sniper to a few meters accuracy at 500 meters range. Plans for improving tracking performance are also described.

  8. Extraordinary energy production after collision of metallic projectile with solid target

    International Nuclear Information System (INIS)

    Production of additional energy in collision of metallic projectile with solid target is considered. It is shown that when the projectile speed exceeds certain threshold, the heat energy after collision may sufficiently exceed the kinetic energy of the projectile

  9. Corrected Launch Speed for a Projectile Motion Laboratory

    Science.gov (United States)

    Sanders, Justin M.; Boleman, Michael W.

    2013-01-01

    At our university, students in introductory physics classes perform a laboratory exercise to measure the range of a projectile fired at an assigned angle. A set of photogates is used to determine the initial velocity of the projectile (the launch velocity). We noticed a systematic deviation between the experimentally measured range and the range…

  10. Development of a numerical model for the ballistic penetration of Fackler gelatine by small calibre projectiles

    Science.gov (United States)

    Gilson, L.; Rabet, L.; Imad, A.; Kakogiannis, D.; Coghe, F.

    2016-05-01

    Among the different material surrogates used to study the effect of small calibre projectiles on the human body, ballistic gelatine is one of the most commonly used because of its specific material properties. For many applications, numerical simulations of this material could give an important added value to understand the different phenomena observed during ballistic testing. However, the material response of gelatine is highly non-linear and complex. Recent developments in this field are available in the literature. Experimental and numerical data on the impact of rigid steel spheres in gelatine available in the literature were considered as a basis for the selection of the best model for further work. For this a comparison of two models for Fackler gelatine has been made. The selected model is afterwards exploited for a real threat consisting of two types of ammunitions: 9 mm and .44 Magnum calibre projectiles. A high-speed camera and a pressure sensor were used in order to measure the velocity decay of the projectiles and the pressure at a given location in the gelatine during penetration of the projectile. The observed instability of the 9 mm bullets was also studied. Four numerical models were developed and solved with LS-DYNA and compared with the experimental data. Good agreement was obtained between the models and the experiments validating the selected gelatine model for future use.

  11. Isospin dependent multifragmentation of relativistic projectiles

    CERN Document Server

    Ogul, R; Atav, U; Buyukcizmeci, N; Mishustin, I N; Adrich, P; Aumann, T; Bacri, C O; Barczyk, T; Bassini, R; Bianchin, S; Boiano, C; Boudard, A; Brzychczyk, J; Chbihi, A; Cibor, J; Czech, B; De Napoli, M; Ducret, J -E; Emling, H; Frankland, J D; Hellstrom, M; Henzlova, D; Imme, G; Iori, I; Johansson, H; Kezzar, K; Lafriakh, A; Le Fèvre, A; Gentil, E Le; Leifels, Y; Luhning, J; Lukasik, J; Lynch, W G; Lynen, U; Majka, Z; Mocko, M; Muller, W F J; Mykulyak, A; Orth, H; Otte, A N; Palit, R; Pawlowski, P; Pullia, A; Raciti, G; Rapisarda, E; Sann, H; Schwarz, C; Sfienti, C; Simon, H; Summerer, K; Trautmann, W; Tsang, M B; Verde, G; Volant, C; Wallace, M; Weick, H; Wiechula, J; Wieloch, A; Zwieglinski, B

    2010-01-01

    The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at SIS. Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the Statistical Multifragmentation Model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios /Z an...

  12. Projectile impact Hugoniot parameters for selected materials

    Energy Technology Data Exchange (ETDEWEB)

    Vigil, M G

    1989-08-01

    The Rankine Hugoniot equation relating the conversion of momentum across a shock front and the empirical relationship for shock velocity as a function of particle velocity are used to calculate the impact pressures for selected materials. The shock velocity and particle velocities are then calculated as a function of impact pressures. The calculated data are graphically presented sets of three figures for the selected materials as follows: Impact pressure as a function of impact velocity, impact pressure as a function of particle velocity, impact pressure as a function of shock velocity. Given the projectile impact velocity and material Hugoniot information, this graphical representation of the data allows for a fast approximation of the impact pressure particle velocity, and shock velocity in the target material. 9 refs., 1 fig., 3 tabs.

  13. Influence of projectile breakup on complete fusion

    Indian Academy of Sciences (India)

    A Mukherjee; M K Pradhan

    2010-07-01

    Complete fusion excitation functions for 11,10B+159Tb and 6,7Li+159Tb have been reported at energies around the respective Coulomb barriers. The measurements show significant suppression of complete fusion cross-sections at energies above the barrier for 10B+159Tb and 6,7Li+159Tb reactions, when compared to those for 11B+159Tb. The comparison shows that the extent of suppression of complete fusion cross-sections is correlated with the -separation energies of the projectiles. Also, the measured incomplete fusion cross-sections show that the -particle emanating channel is the favoured incomplete fusion process. Inclusive measurement of the -particles produced in 6Li+159Tb reaction has been carried out. Preliminary CDCC calculations carried out to estimate the - yield following 6Li breaking up into + fail to explain the measured -yield. Transfer processes seem to be important contributors.

  14. A study of the penetration of projectiles into marine sediments

    International Nuclear Information System (INIS)

    The work described in this document consists of three main parts: - Application, after having reviewed calculation methods and known codes, of a dynamic plasticity model based on the upper bound-method (with dissipated energy calculations by plastic deformations). The soil model used for this calculation is the Cambridge Clay Model. - Carrying out a programme of tests with instrumented small scale penetrators in centrifuge on a consolidated clay-target. The trials are done under 50 g, with projectiles, fired with an airgun at high impact velocity (50 m/s). The penetrators' instrumentation consists of either measuring acceleration, or tip force with strain gauges. - The mounting of a small instrumented penetrator for shallow water depth experimentations, with an accelerometer, and a local cell for tip resistance. A rapid electronic data acquisition system has been developed for these experimentations. The preliminary tests are done in a large tank filled with clay. The geotechnical characteristics of the clay are perfectly controlled. The tests performed under these conditions have shown the following observations: the rapid electronic data acquisition system works perfectly and could be used as a basic component for a deep water instrumentated penetrator; the results, obtained in these particular test conditions, are in a perfect agreement with the predictions of the model developed in the frame of this contract

  15. NUMERICAL SIMULATION FOR FORMED PROJECTILE OF DEPLETED URANIUM ALLOY

    Institute of Scientific and Technical Information of China (English)

    宋顺成; 高平; 才鸿年

    2003-01-01

    The numerical simulation for forming projectile of depleted uranium alloy with the SPH ( Smooth Particle Hydrodynamic ) algorithm was presented. In the computations the artificial pressures of detonation were used, i. e. , the spatial distribution and time distribution were given artificially. To describe the deformed behaviors of the depleted uranium alloy under high pressure and high strain rate, the Johnson-Cook model of materials was introduced. From the numerical simulation the formed projectile velocity,projectile geometry and the minimum of the height of detonation are obtained.

  16. Study of momentum distributions for projectile fragments of 22Ne and 28Si nuclei in collisions with emulsion

    International Nuclear Information System (INIS)

    The charge and mass yield curves and the momentum distributions of the projectile fragments produced in the interactions of 4.1 A GeV/c 22Ne and 4.5 A GeV/c 28Si with emulsion have been studied. The overall charge distributions of the projectile fragments resulting from these interactions are presented. The dependence of the mass yield distributions of the projectile fragments on the impact parameter has been tested. The momentum distributions for the considered reactions have been investigated by two methods. First, the projected momentum distributions in the plane of the microscope have been achieved by fitting the projected angular distributions to gaussian ones. It has been found that the width of the distribution changes with the charge of the projectile fragment and it decreases with the increase of the projectile fragment charge. Secondly, the transverse momentum distributions have been compared with previous studies. The momentum distribution, in the forward cone, is a typically narrow gaussian one

  17. Comparison Among Depths of Penetration of Different Targets Subjected to Rigid Projectile Impact

    Institute of Scientific and Technical Information of China (English)

    LI Jicheng; CHEN Xiaowei

    2008-01-01

    The ratios of depth of penetration (DOP) of different targets under the same penetration condition was investigated according to the dimensionless formula of DOP of different targets penetrated by a non-deformable projectile.Results show that various targets may be equivalent to each other.The applicable range of the equivalence and the feasibility of targets substitution were discussed by integrating the available test data.

  18. Penetration of a Small Caliber Projectile into Single and Multi-layered Targets

    Directory of Open Access Journals (Sweden)

    Riad A.M.

    2010-06-01

    Full Text Available The normal penetration of armor-piercing projectiles into single and multi-layered steel plates has been investigated. An experimental program has been conducted to study the effect of spaced and in-contact layered targets on their ballistic resistance. Armor piercing projectiles with caliber of 7.62 mm were fired against a series of single and multi-layered steel targets. The projectile impact velocities were ranged from 300-600 m/s, whereas the total thicknesses of the tested single, spaced and in-contact layered steel targets were 3 mm. The penetration process of different tested target configurations has been simulated using Autodayn-2D hydrocode. The experimental measurements of the present work were used to discuss the effect of impact velocity, target configurations and number of layers of different spaced and in-contact layered steel targets on their ballistic resistance. In addition, the post-firing examination of the tested targets over the used impact velocity range showed that the single and each layer of spaced and in-contact laminated steel targets were failed by petalling. Finally, the obtained experimental measurements were compared with the corresponding numerical results of Autodyn-2D hydrocode, good agreement was generally obtained.

  19. Simultaneous Projectile-Target Excitation in Heavy Ion Collisions

    OpenAIRE

    Benesh, C. J.; Friar, J. L.

    1994-01-01

    We calculate the lowest-order contribution to the cross section for simultaneous excitation of projectile and target nuclei in relativistic heavy ion collisions. This process is, to leading order, non-classical and adds incoherently to the well-studied semi-classical Weizs\\"acker-Williams cross section. While the leading contribution to the cross section is down by only $1/Z_P$ from the semiclassical process, and consequently of potential importance for understanding data from light projectil...

  20. Theoretical design and modeling of an Infantry railgun projectile

    OpenAIRE

    Brady, James A.

    2005-01-01

    In order for railgun technology to be relevant to the Infantry, the design of the projectile must incorporate the following three concepts: an effective ballistics package, geometries for aerodynamic stability; and a non-parasitic conducting armature. I designed an effective 30mm and scaled 40mm projectile which incorporates the aforementioned concepts. My ballistics analysis concluded with two AUTODYN. finite-element computer models that refined theoretical estimates for target penetration. ...

  1. Analysis of Penetration Model for Geo-Material by Rigid Projectile

    Institute of Scientific and Technical Information of China (English)

    LI Jianchun; MA Guowei; YU Maohong

    2006-01-01

    Based on the cylindrical cavity expansion theory,a plastic-damage-elastic model is proposed for the penetration problem of geo-material.In the model,the unified strength criterion (Yu,1991) is adopted as the failure criterion.The distributions of the radial stress and velocity are analyzed.According to the Newton's second law,a series results of the final penetration depth and the impedance load are obtained to different parameter b,when a rigid projectile normally impacts and penetrates a semi-infinite geo-material target with an impact velocity of 300-1 200 m/s.By comparing with the test data available,it appears that the method can be used in analyzing the final depth and the impedance load of a rigid projectile penetrating into a semi-infinite target with different impact velocities.

  2. Effect of CFRP strengthening on the response of RC slabs to hard projectile impact

    Energy Technology Data Exchange (ETDEWEB)

    Almusallam, Tarek; Al-Salloum, Yousef; Alsayed, Saleh; Iqbal, Rizwan; Abbas, Husain, E-mail: abbas_husain@hotmail.com

    2015-05-15

    Highlights: • Studied response of CFRP-strengthened RC slabs under the impact load. • Slabs were tested under the strike of hemispherical steel projectiles at varying impact. • The slabs were analyzed numerically using LS-DYNA. • Strengthening increased the ballistic limit velocity by 18% and perforation energy by 56.7%. • CFRP sheet reduced the crater damage and contained the flying concrete fragments. - Abstract: In this paper impact response of CFRP-strengthened RC panels under the impact of non-deformable projectiles has been presented. The control and CFRP-strengthened RC slab panels were tested under the strike of hemispherical nosed steel projectiles at varying impact velocities. The response of these panels was investigated experimentally as well as numerically. The damage of the slab panels was measured in terms of the penetration depth, formation of cracks, spalling and scabbing areas and fracture of CFRP sheet. This study presents a practical and efficient numerical method for analyzing the impact response of CFRP-strengthened RC structures using LS-DYNA. The CFRP strengthening was found to increase the ballistic limit velocity by 18%, perforation energy of RC slabs by 56.7%, reduce the front crater damage and contains the flying of concrete fragments from the rear face. The maximum impact force occurs at almost same penetration depth for the control and CFRP-strengthened slabs but the restraint provided by CFRP increased the penetration depth by about 1/19.3 of the thickness of slab.

  3. Study on the oblique perforation of thin steel pates by flat and ogival projectiles

    Science.gov (United States)

    Guo, Zitao; Zhang, Wei; Ren, Peng; Hypervelocity Impact Research Center Collaboration

    This paper presents a numerical study on the oblique perforation of thin steel plates. Numerical simulations of 1 mm single A3 steel plates impacted by flat and ogival projectiles at 0°, 15°, 30°, 45° and 60° angles over a range of velocities from 50 to 250 m/s were performed using the finite element code ABAQUS, where a modified versions of the J-C constitutive relation and fracture criterion based on a series of quasi-static and dynamic tensile tests with smooth and notched axisymmetric specimens were adopted to approximate behaviors of target material. Corresponding oblique perforation experiments were also conducted in order to be compared and calibrated. Initial-residual velocity curves and ballistic limits of targets under different angle impact were determined and compared, and the effects of projectile nose shape and obliquity on the ballistic resistance and failure models of targets were investigated. Results show that the nose shape of the projectile and oblique angles severely affected both the energy absorption and the failure mode of the target plate during perforation. Good agreement is found between the numerical simulations and experimental results.

  4. Electromagnetic Dissociation of Target Nuclei by $^{16}$O and $^{32}$S Projectiles

    CERN Multimedia

    2002-01-01

    We have measured the inclusive cross sections for electromagnetic dissociation (ED) of |1|9|7Au targets by 60 and 200~GeV/nucleon |1|6O and 200~ GeV/nucleon |3|2S projectiles. This is an extension of similar measurements carried out earlier at 2~GeV/nucleon. ED is a purely electromagnetic process occuring when a virtual photon is exchanged between projectile and target. The experiment emphasized precise measurement of total one-neutron-out cross sections. A secondary goal was to test the applicability of the concepts of factorization and limiting fragmentation at ultrarelativistic energies.\\\\ \\\\ Each individual target will be irradiated upstream and parasitic to experiment NA38 on the dimuon spectrometer. Cross sections for reactions of interest will be determined by off-line counting of the appropriate residual @g~ray activities in Ames, Iowa, USA. Preliminary results indicate an ED one-neutron removal cross section for 200~GeV/nucleon |1|6O projectiles on |1|9|7Au of approximately 0.45~barns. The result is ...

  5. A Mass Loss Penetration Model to Investigate the Dynamic Response of a Projectile Penetrating Concrete considering Mass Abrasion

    Directory of Open Access Journals (Sweden)

    NianSong Zhang

    2015-01-01

    Full Text Available A study on the dynamic response of a projectile penetrating concrete is conducted. The evolutional process of projectile mass loss and the effect of mass loss on penetration resistance are investigated using theoretical methods. A projectile penetration model considering projectile mass loss is established in three stages, namely, cratering phase, mass loss penetration phase, and remainder rigid projectile penetration phase.

  6. Set Down Study of Projectile in Flight Through Imaging

    Directory of Open Access Journals (Sweden)

    Suman Kumar Choudhury

    2014-11-01

    Full Text Available Deformation study of projectile immediately after firing is essential for its successful impact. A projectile that undergoes more than the tolerated amount of deformation in the barrel may not produce the requisite results. The study of projectile deformation before its impact requires it to be imaged in flight and perform some computation on the acquired image. Often the deformation tolerance is of the order of tens of micrometer and the acquired image cannot produce image with such accuracy because of photographic limitations. Therefore, it demands sub-pixel manipulation of the captured projectile image. In this work the diameter of a projectile is estimated from its image which became blur because of slow shutter speed. First the blurred image is restored and then various interpolation methods are used for sub-pixel measurement. Two adaptive geometrical texture based interpolation schemes are also proposed in this research. The proposed methods produce very good results as compared to the existing methods.Science Journal, Vol. 64, No. 6, November 2014, pp.530-535, DOI:http://dx.doi.org/10.14429/dsj.64.8114

  7. Elastic recovery in targets impacted by low-velocity projectiles*%信息动态

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    By taking into account the whole plastic deformation and elastic deformation recovery of targets during the penetration of the rigid, sharp-nose projectiles, the ANSYS/LS-DYNA code was used to calculate the rebound velocities of the projectiles and targets in the cases that the projectiles at the same velocities penetrated into the targets with different widths and thicknesses. Influences of the sizes of the targets and the impact velocities of the projectiles on the elastic recovery of the targets and the rebound of the projectiles were analyzed. The researched results are helpful for the engineering and experimental designs of the projectiles with low velocities penetrating into the targets.

  8. Design limitations for small caliber electromagnetic saboted rod projectiles

    International Nuclear Information System (INIS)

    In any application of electromagnetic launch, the armature package must conform to the barrel and provide the desired terminal performance. Finned long rod projectiles have proven to be viable candidates for both flight bodies and terminal effectiveness. This paper describes the criteria necessary for integrating a solid armature with a conventional type finned rod. An initial design is presented for a rod projectile, launched from a 15.24 mm (.60 caliber) augmented railgun with a sinusoidal driving current. Other designs are assessed in order to explore improvements and scalability to other bore diameters. The authors evaluate the final armature design considering: launch, flight, and terminal effects. ohmic heating, structural limitations, and barrel parameters are also discussed. Flight and aerodynamic data are scaled from existing finned rod projectile data bases to calculate horizontal flat-trajectory performance. Finally, terminal effects are incorporated for a simple rolled homogeneous armor (RHA) target

  9. Oblique perforation of thick metallic plates by rigid projectiles

    Institute of Scientific and Technical Information of China (English)

    Xiaowei Chen; Qingming Li; Saucheong Fan

    2006-01-01

    Oblique perforation of thick metallic plates by rigid Drojectiles with various nose shapes is studied in this paper.Two perforation mechanisms,i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose,are considered in the proposed analytical model.It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers,i.e., the impact function,the geometry function of projectile,the non-dimensional thickness of target and the impact obliquity.Explicit formulae are obtained to predict the ballistic limit.residual velocity and directional change for the oblique perforation of thick metallic plates.The proposed model is able to predict the critical condition for the occurrence of ricochet.The proposed model is validated by comparing the predictions with other existing models and independent experimental data.

  10. Fragmentation of Pb-Projectiles at SPS Energies

    CERN Multimedia

    2002-01-01

    % EMU17 \\\\ \\\\ We have exposed stacks consisting of solid state nuclear track detectors (CR-39 plastic and BP-1 glass) and different target materials at the SPS to beams of Pb projectiles. Our detectors record tracks of relativistic nuclei with charge numbers of Z~$\\geq$~6 for CR-39 and Z~$\\geq$75 for BP-1. After development of the tracks by etching they are detected and measured using completely automated microscope systems. Thus experiments with high statistics are possible. \\\\ \\\\BP-1 detectors were exposed to measure total charge changing cross sections and elemental production cross sections for heavy projectile fragments. These experiments were performed for different targets CH$ _{2} $, C, Al, Cu, Ag and Pb. Comparison of the results for different targets allows to investigate contributions to charge changing reactions by electromagnetic dissociation. Multifragmentation events in which several intermediate mass fragments are emitted from the heavy Pb projectile are studied using stacks containing CR-39 d...

  11. Optical potentials for p-shell heavy ion projectiles

    International Nuclear Information System (INIS)

    Elastic and inelastic scatterings of 12C, 13C, 14N, and 16O projectiles on 28Si have been studied at corresponding bombarding energies to the scattering in regions of the vicinity of the strong absorption radius. Optical model and microscopic double-folding model analyses have been performed in order to define the nature of the optical potential depending on the projectiles. The analysis by the optical model calculations showed that the shallow potential (V/sub R/ = 10 MeV) was not adequate for reproducing both the measured elastic and inelastic angular distributions, and a spin-dependent noncentral potential for the scattering systems 13C,14N+28Si was indispensable for obtaining the similar central potentials for all four projectiles. Analysis by the microscopic double-folding calculations supported the results of the optical model calculations

  12. Projectile transverse motion and stability in electromagnetic induction launchers

    Energy Technology Data Exchange (ETDEWEB)

    Shokair, I.R.

    1993-12-31

    The transverse motion of a projectile in an electromagnetic induction launcher is considered. The equations of motion for translation and rotation are derived assuming a rigid projectile and a flyway restoring force per unit length that is proportional to the local displacement. Linearized transverse forces and torques due to energized coils are derived for displaced or tilted armature elements based on a first order perturbation method. The resulting equations of motion for a rigid projectile composed of multiple elements in a multi-coil launcher are analyzed as a coupled oscillator system of equations and a simple linear stability condition is derived. The equations of motion are incorporated into the 2-D Slingshot circuit code and numerical solutions for the transverse motion are obtained. For a launcher with a 10 cm bore radius with a 40 cm long solid armature, we find that stability is achieved with a restoring force (per unit length) constant of k {approx} 1 {times} 10{sup 8} N/m{sup 2}. For k = 1.5 {times} 10{sup 8} N/m{sup 2} and sample coil misalignment modeled as a sine wave of 1 mm amplitude at wavelengths of one or two meters, the projectile displacement grows to a maximum of 4 mm. This growth is due to resonance between the natural frequency of the projectile transverse motion and the coil displacement wavelength. This resonance does not persist because of the changing axial velocity. Random coil displacement is also found to cause roughly the same projectile displacement. For the maximum displacement a rough estimate of the transverse pressure is 50 bars. Results for a wound armature with uniform current density throughout show very similar displacements.

  13. Dimensional Analysis on the Perforation of Stiffened Plates by Projectiles

    Institute of Scientific and Technical Information of China (English)

    SONG Wei-dong; NING Jian-guo

    2007-01-01

    The phenomena attendant to the perforation of truncated oval shape projectile in to multi-layered stiffened plates were investigated. Dimensional analysis was employed to give an empirical formula. Then a membership function was introduced to modify the empirical formula. The effects of initial velocities, base plate thicknesses, height and width of stiffener on residual velocities were explored. The predictions of the empirical formula are in reasonably good agreement with those of experiment and numerical results. All these results indicate that the empirical formula is capable of predicting the residual velocity of the projectile penetrating the multi-layered stiffened plates.

  14. PERFORATION OF PLASTIC SPHERICAL SHELLS UNDER IMPACT BY CYLINDRICAL PROJECTILES

    Institute of Scientific and Technical Information of China (English)

    NING Jian-guo; SONG Wei-dong

    2006-01-01

    The objective is to study the perforation of a plastic spherical shell impacted by a cylindrical projectile. First, the deformation modes of the shell were given by introducing an isometric transformation. Then, the perforation mechanism of the shell was analyzed and an analytical model was advanced. Based on Hamilton principle, the governing equation was obtained and solved using Runge-Kuta method. Finally, some important theoretical predictions were given to describe the perforation mechanism of the shell. The results will play an important role in understanding the perforation mechanism of spherical shells impacted by a projectile.

  15. High-precision Penning trap mass measurements of 'difficult' elements produced via projectile fragmentation with LEBIT

    Energy Technology Data Exchange (ETDEWEB)

    Ringle, R., E-mail: ringle@nscl.msu.edu; Bachelet, C.; Barquest, B. R.; Block, M.; Bollen, G.; Campbell, C. M.; Facina, M.; Ferrer, R.; III, C. M. Folden; Guenaut, C.; Kwan, E.; Kwiatkowski, A. A.; Lincoln, D. L.; Morrissey, D. J.; Pang, G. K.; Prinke, A. M.; Savory, J.; Schury, P.; Schwarz, S.; Sumithrarachchi, C. S. [National Superconducting Cyclotron Laboratory (United States)

    2011-07-15

    Rare isotope beams of many elements can be difficult or impossible to obtain at ISOL facilities due to their high melting points or chemical reactivity, but they are easily produced by projectile fragmentation and in-flight separation, a technique that rapidly produces fragments lighter than the projectile in a chemistry-free manner. Until recently, such high-energy projectile fragments could not be reduced to the thermal energies necessary for precision mass measurements in Penning traps. The Low Energy Beam and Ion Trap (LEBIT) facility at the National Superconducting Cyclotron Laboratory (NSCL) has demonstrated that projectile fragment beams can be thermalized and measured in a high-precision Penning trap. Since 2005, over 30 isotopes have been measured with LEBIT, including several isotopes of elements which are difficult for ISOL facilities to produce, such as Fe, Co, Si, Br, and S. These measurements have contributed to our understanding of nuclear structure, nuclear astrophysics, and fundamental symmetries. Some recent highlights include the discovery of an isomeric state in {sup 65}Fe, testing the Isobaric Mass Multiplet Equation (IMME) with the A = 32, T = 2 quintet with a measurement of {sup 32}Si, probing out to the proton dripline with {sup 70m}Br, and studying the N = 28 shell closure with measurements of {sup 40 - 44}S. Results of these measurements will be discussed, along with the technical developments which made them possible.

  16. Testing the Accuracy of a Projectile Motion Apparatus

    Science.gov (United States)

    Henderson, Bret; Martell, Eric

    2013-03-01

    The purpose of this research is to predict where a ball would land given initial velocity, angular velocity, and atmospheric conditions. A spinning spherical object flying through air is affected by gravity, quadratic drag forces, and the Magnus force. Mathematica was used to numerically solve predictions for the equations of motion. These predictions were compared with experimental data gathered by launching tennis balls, baseballs, and/or soccer balls from a machine we designed to propel the balls with a pre-determined initial velocity and initial angular velocity.

  17. MEMIN: Chemical Modification of Projectile Spheres, Target Melts and Shocked Quartz in Hypervelocity Impact Experiments

    Science.gov (United States)

    Ebert, M.; Hecht, L.; Deutsch, A.; Kenkmann, T.

    2011-03-01

    We present results of hypervelocity cratering experiments using iron meteorite as projectile and a sandstone target. The ejecta show shock features (melting, PDFs, lechatelierite) and physical as well as chemical mixing between projectile and target.

  18. On the Trajectories of Projectiles Depicted in Early Ballistic Woodcuts

    Science.gov (United States)

    Stewart, Sean M.

    2012-01-01

    Motivated by quaint woodcut depictions often found in many late 16th and 17th century ballistic manuals of cannonballs fired in air, a comparison of their shapes with those calculated for the classic case of a projectile moving in a linear resisting medium is made. In considering the asymmetrical nature of such trajectories, the initial launch…

  19. Survivability of Meteorite Projectiles - Results from Impact Experiments

    Science.gov (United States)

    Bland, P. A.; Cintala, M. J.; Hoerz, F.; Cressey, G.

    2001-01-01

    An experimental impact study investigating the fragmentation of various projectiles, including meteorite, at speeds up to 1.8 km/s. The results have implications for the survivability of meteorites impacting planetary and asteroidal surfaces. Additional information is contained in the original extended abstract.

  20. Projectile deformation effects in the breakup of $^{37}$Mg

    CERN Document Server

    Shubhchintak,; Shyam, R

    2015-01-01

    We study the breakup of $^{37}$Mg on Pb at 244MeV/u with the recently developed extended theory of Coulomb breakup within the post-form finite range distorted wave Born approximation that includes deformation of the projectile. Comparing our calculated cross section with the available Coulomb breakup data we determine the possible ground state configuration of $^{37}$Mg.

  1. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based…

  2. Behaviour of a Kinetic Energy Projectile on Angular Impact

    Directory of Open Access Journals (Sweden)

    R. A. Goel

    1988-07-01

    Full Text Available Experiments of high velocity impact have been carried out with 30 mm armoured piercing projectiles on 55 mm thick hard steel plate. Angle of impact has been varied from 10" to 90". Damage inflicted on target with varying angle of impact has been reported and discussed in this paper. Comparative behaviour with 20 mm APP shot has also been discussed.

  3. Calculation of forces arising from impacting projectiles upon yielding structures

    International Nuclear Information System (INIS)

    Calculations concerning the impact of airplanes upon nuclear power plant buildings usually imply that the building [QUOTE]acts' as a rigid target. This assumption is justified for considerations concerning the structural integrity of the building being hit. However, for investigating induced vibrations of components within the structure, this approach might-in general-be too conservative. It is expected, that yielding of the structure during impact reduces the peak values of the loads and changes the temporal behaviour of the load function which is obtained for a rigid target. To calculate the changes of the load function which are due to deformations of the structure, Riera's method is extended for the case of a yielding target. The calculations are performed with a one-dimensional model for the projectile. The presented model calculations seem to verify that the motion of the target does not have much influence on the impact force for projectiles similar to the model projectile, provided the displacement of the yielding target is small in comparison with the path covered by the free-flying projectile during a time which is equivalent to the total time of impact. (Auth.)

  4. 3D Numerical Simulation of Projectile Penetration into Concrete Target

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Basing on the explicit instantaneous dynamics software MSC-Dytran and the general coupling arithmetic, the process of the projectile penetration into concrete target was simulated with the point-line-surface-body modeling method. Simulation results are in agreement with experimental results. The simulated data could provide design reference for the defense engineering construction and penetrator design.

  5. Predicting the fragmentation onset velocity for different metallic projectiles using numerical simulations

    NARCIS (Netherlands)

    Livingstone, I.H.G.; Verolme, K.; Hayhurst, C.J.

    2001-01-01

    For cubes and spheres under high velocity impact there exists for each system of projectile and target, a threshold velocity that is just sufficient to shatter the projectile. This velocity, usually above 2km/s for metallic projectiles, is known as the fragmentation onset velocity. To determine the

  6. Wound Ballistics Modeling for Blast Loading Blunt Force Impact and Projectile Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Paul A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cooper, Candice Frances [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Burnett, Damon J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Light body armor development for the warfighter is based on trial-and-error testing of prototype designs against ballistic projectiles. Torso armor testing against blast is virtually nonexistent but necessary to ensure adequate protection against injury to the heart and lungs. In this report, we discuss the development of a high-fidelity human torso model, it's merging with the existing Sandia Human Head-Neck Model, and development of the modeling & simulation (M&S) capabilities necessary to simulate wound injury scenarios. Using the new Sandia Human Torso Model, we demonstrate the advantage of virtual simulation in the investigation of wound injury as it relates to the warfighter experience. We present the results of virtual simulations of blast loading and ballistic projectile impact to the tors o with and without notional protective armor. In this manner, we demonstrate the ad vantages of applying a modeling and simulation approach to the investigation of wound injury and relative merit assessments of protective body armor without the need for trial-and-error testing.

  7. Experimental Research on Behavior of Composite Material Projectile Penetrating Concrete Target

    Institute of Scientific and Technical Information of China (English)

    ZHONG Weizhou; SONG Shuncheng; ZHANG Fangju; ZHANG Qingping; HUANG Xicheng; LI Sizhong; LU Yonggang

    2008-01-01

    Projectile made of carbon fiber composite material shell and metal warhead penetrates concrete target at speeds of 336 m/s, 447 m/s and 517 m/s.The angles between the perpendicular of target surface and projectile axis are 0° and 30° .The thickness of concrete target is 200 mm and the compression strength is 30 MPa.The experimental results indicate that the strength of composite material structure is high.Composite projectile can go through concrete target without fiber segregation and breakage.The percent fill is 18.5% in the composite material projectile.It is about twice as that of metal projectile, if the density of metal is taken as 7.8 g/cm3.Comparing with metal projectile, low-density, high-strength composite material can lessen projectile weight, improve charge-weight ratio of detonator and enhance destructive powder.

  8. Performance of primary repair on colon injuries sustained from low-versus high-energy projectiles.

    Science.gov (United States)

    Lazovic, Ranko; Radojevic, Nemanja; Curovic, Ivana

    2016-04-01

    Among various reasons, colon injuries may be caused by low- or high-energy firearm bullets, with the latter producing a temporary cavitation phenomenon. The available treatment options include primary repair and two-stage management, but recent studies have shown that primary repair can be widely used with a high success rate. This paper investigates the differences in performance of primary repair on these two types of colon injuries. Two groups of patients who sustained colon injuries due to single gunshot wounds, were retrospectively categorized based on the type of bullet. Primary colon repair was performed in all patients selected based on the inclusion and exclusion criteria (Stone and Fabian's criteria). An almost absolute homogeneity was attained among the groups in terms of age, latent time before surgery, and four trauma indexes. Only one patient from the low-energy firearm projectile group (4%) developed a postsurgical complication versus nine patients (25.8%) from the high-energy group, showing statistically significant difference (p = 0.03). These nine patients experienced the following postsurgical complications: pneumonia, abscess, fistula, suture leakage, and one multiorgan failure with sepsis. Previous studies concluded that one-stage primary repair is the best treatment option for colon injuries. However, terminal ballistics testing determined the projectile's path through the body and revealed that low-energy projectiles caused considerably lesser damage than their high-energy counterparts. Primary colon repair must be performed definitely for low-energy short firearm injuries but very carefully for high-energy injuries. Given these findings, we suggest that the treatment option should be determined based not only on the bullet type alone but also on other clinical findings. PMID:26874437

  9. Temporary cavity created by free-flying projectiles propelled from a powder-actuated nail gun.

    Science.gov (United States)

    Frank, Matthias; Schönekeß, Holger C; Jäger, Frank; Hertel, Heinz; Ekkernkamp, Axel; Bockholdt, Britta

    2012-09-01

    Nails and driving pins discharged from powder-actuated fastening tools bear some special ballistic characteristics. Compared to the usual pistol or revolver projectiles, the sectional density (S) of fastening pins is extremely high. The general prevailing opinion is that the kinetic energy delivered by fastening tools is not high enough to cause a temporary cavity. Therefore, it was the aim of this study to investigate the wound morphology due to fastening bolts discharged from a powder-actuated direct-acting nail gun (where, in contrast to modern piston-type tools, the expanding gases act directly on the fastener) using ballistic soap blocks as simulants. For test shots, a direct-acting powder-actuated nail gun which features three interchangeable barrels (caliber (cal.) 6, 8, and 10 mm) was used. The average kinetic energy was 537, 532, and 694 J for the 6-, 8-, and 10-mm cal. bolts, respectively. Test shots on the ballistic soap blocks demonstrated that free-flying projectiles discharged from direct-acting fastening tools are able to create a temporary cavity. PMID:22797891

  10. Ballistics considerations for small-caliber, low-density projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Gouge, M.J.; Baylor, L.R.; Combs, S.K.; Fisher, P.W.; Foster, C.A.; Foust, C.R.; Milora, S.L.; Qualls, A.L.

    1993-11-01

    One major application for single- and two-stage light gas guns is for fueling magnetic fusion confinement devices. Powder guns are not a feasible alternative due to possible plasma contamination by residual powder gases and the eventual requirement of steady-state operation at {approximately} 1 Hz, which will dictate a closed gas handling system where propellant gases are recovered, processed and recompressed. Interior ballistic calculations for single-stage light gas guns, both analytical and numerical, are compared to an extensive data base for low density hydrogenic projectiles (pellets). Some innovative range diagnostics are described for determining the size and velocity of these small (several mm) size projectiles. A conceptual design of a closed cycle propellant gas system is presented including tradeoffs between different light propellant gases.

  11. Plasma as a high-charge-state projectile stripping medium

    International Nuclear Information System (INIS)

    The classical trajectory Monte Carlo model has been used to computationally study the charge-state distributions that result from interactions between a high-energy, multielectron projectile and neutral and fully ionized targets. These studies are designed to determine the properties of a plasma for producing highly stripped ions as a possible alternative to gas and foil strippers that are commonly used to enhance the charge states of energetic ion beams. The results of these studies clearly show that a low-atomic-number, highly ionized plasma can yield higher charge states than a neutral target of the same density. The effect is principally attributable to the reduction in the number of available electron-capture channels. In this article, we compare the charge-state distributions that result during passage of a 20-MeV Pb projectile through neutral gas and fully ionized (singly charged) plasma strippers and estimate the effects of multiple scattering on the quality of the beam

  12. Performance of the Projectile Fragmentation Wall at CELSIUS Storage Ring

    Science.gov (United States)

    Siwek, A.; Budzanowski, A.; Czech, B.; Gburek, T.; Jakobsson, B.; Kozik, E.; Skwirczyńska, I.; Westerberg, L.

    The projectile fragmentation wall [Budzanowski, A. et al., Nucl. Instr. Meth. A482, 528 (2002).] (PFW) is a part of a bigger detection system comprising of the CHICSi detector [Jakobsson, B., Nucl. Phys. News Int. 9:2, 22 (1999). Siwek, A., Nucl. Phys., A654, 2695 (1999)] and a recoil detectors array [Kuznetsov, A. V. et al, Nucl. Instr. Meth. A452, 525 (2000)]. The system is designed to register products of proton- and heavy ion-induced reactions at the energies 50-450 MeV/nucleon (see Bo Jakobsson's contribution to this conference). The aim of PFW is to register and identify projectile like fragments emitted in forward direction not covered by the CHICSi detector.

  13. Mechanisms of Li-projectile breakup-up

    International Nuclear Information System (INIS)

    Various experimental and theoretical features observed in recent studies of break-up of 6Li and 7Li projectiles in the field of atomic nuclei are discussed, in particular for the transitional energy regime of 10-30 MeV/amu. The discussion is organized as three independent lectures presented at the International School on Nuclear Physics, Kiev (UkSSR), 28 May - 8 June, 1990. After a survey on the main experimental facts and on the basic reaction mechanisms, current theoretical approaches are illustrated by an application to the analysis of elastic break-up of 156 MeV 6Li projectiles. Finally Coulomb break-up is discussed as a novel tool of laboratory nuclear astrophysics. (orig.)

  14. Magnus Force of Common Projectile Bodies with Turbulent Layers

    Institute of Scientific and Technical Information of China (English)

    CHEN Jun

    2005-01-01

    Calculating formulae of Magnus force on common projectile bodies (cone-shaped and parabola-shaped) with turbulent layers were built based on Magnus theory. The effects of temperature exponential were considered, and curve-fitting approaches were adopted in the research that could give more exact result data. Both flow layer constants and shape constants are presented in Magnus force formulae, which are useful to evaluate Magnus force in different states.

  15. Projectile and Lab Frame Differential Cross Sections for Electromagnetic Dissociation

    Science.gov (United States)

    Norbury, John W.; Adamczyk, Anne; Dick, Frank

    2008-01-01

    Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

  16. Numerical simulation of multiphase cavitating flows around an underwater projectile

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The present simulation investigates the multiphase cavitating flow around an underwater projectile.Based on the Homogeneous Equilibrium Flow assumption,a mixture model is applied to simulate the multiphase cavitating flow including ventilated cavitation caused by air injection as well as natural cavitation that forms in a region where the pressure of liquid falls below its vapor pressure. The transport equation cavitating model is applied.The calculations are executed based on a suite of CFD code.The hyd...

  17. Projectile - Mass asymmetry systematics for low energy incomplete fusion

    Directory of Open Access Journals (Sweden)

    Singh Pushpendra P.

    2015-01-01

    Full Text Available In the present work, low energy incomplete fusion (ICF in which only a part of projectile fuses with target nucleus has been investigated in terms of various entrance channel parameters. The ICF strength function has been extracted from the analysis of experimental excitation functions (EFs measured for different projectile-target combinations from near- to well above- barrier energies in 12C,16O(from 1.02Vb to 1.64Vb+169Tm systems. Experimental EFs have been analysed in the framework statistical model code PACE4 based on the idea of equilibrated compound nucleus decay. It has been found that the value of ICF fraction (FICF increases with incident projectile energy. A substantial fraction of ICF (FICF ≈ 7 % has been accounted even at energy as low as ≈ 7.5% above the barrier (at relative velocity νrel ≈0.027 in 12C+169Tm system, and FICF ≈ 10 % at νrel ≈0.014 in 16O+169Tm system. The probability of ICF is discussed in light of the Morgenstern’s mass-asymmetry systematics. The value of FICF for 16O+169Tm systems is found to be 18.3 % higher than that observed for 12C+169Tm systems. Present results together with the re-analysis of existing data for nearby systems conclusively demonstrate strong competition of ICF with CF even at slightly above barrier energies, and strong projectile dependence that seems to supplement the Morgenstern’s systematics.

  18. Yields of Projectile Fragments in Sulphur-Emulsion Interactions at 3.7 GeV/nucleon

    CERN Document Server

    Kamel, S; Fayed, M

    2016-01-01

    This work presents the basic characteristics of singly, doubly and heavily charged projectile fragments emitted in inelastic interactions of 32S ions with photo-emulsion nuclei at Dubna energy (3.7 GeV/nucleon). The relationship between the projectile mass and the charge of the projectile fragments is investigated, reflecting the importance of the projectile size. The mean multiplicities of different charged projectile fragments are studied and are found to increase linearly with the projectile mass. The yields of projectile fragments broke up from the interactions of 32S projectile nuclei with the different target nuclei in a nuclear emulsion are studied and they indicate that the projectile breakup mechanism seems to be independent of the target mass. A study of the multiplicity distributions of singly and doubly charged projectile fragments seem to be energy independent.

  19. Chunk projectile launch using the Sandia Hypervelocity Launcher Facility

    Energy Technology Data Exchange (ETDEWEB)

    Chhabildas, L.C.; Trucano, T.G.; Reinhart, W.D.; Hall, C.A.

    1994-07-01

    An experimental technique is described to launch an intact ``chunk,`` i.e. a 0.3 cm thick by 0.6 cm diameter cylindrical titanium alloy (Ti-6Al-4V) flyer, to 10.2 km/s. The ability to launch fragments having such an aspect ratio is important for hypervelocity impact phenomenology studies. The experimental techniques used to accomplish this launch were similar but not identical to techniques developed for the Sandia HyperVelocity Launcher (HVL). A confined barrel impact is crucial in preventing the two-dimensional effects from dominating the loading response of the projectile chunk. The length to diameter ratio of the metallic chunk that is launched to 10.2 km/s is 0.5 and is an order of magnitude larger than those accomplished using the conventional hypervelocity launcher. The multi-dimensional, finite-difference (finite-volume), hydrodynamic code CTH was used to evaluate and assess the acceleration characteristics i.e., the in-bore ballistics of the chunky projectile launch. A critical analysis of the CTH calculational results led to the final design and the experimental conditions that were used in this study. However, the predicted velocity of the projectile chunk based on CTH calculations was {approximately} 6% lower than the measured velocity of {approximately}10.2 km/S.

  20. Theoretical Design and Computational Fluid Dynamic Analysis of Projectile Intake

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2011-08-01

    Full Text Available With the development of the science and technology, the more requirements such as cost effective, high specific impulse in wide operation rang, becomes stricter and multiplicity. However, the existing supersonic inlet can no longer adjust to all the new projectiles. In this paper, based on the basic characteristic of inlet and considering the design requirements, the two-dimensional supersonic projectile inlet was designed and verified by numerical simulation under different operating conditions such as attack angle, altitude, and so on. The results are shown that: 1 The design process is successful, but the working conditions should be limited to the small angle of attack; 2 The total pressure recovery coefficient is increasing as the Ma number increases, and then is gradually decreased after the point of Mach number is equal to 0.5; 3 The existence of attack angle reduces values of total pressure recovery. And moreover, the shock wave which occurs at the anterior point is gradually deviating from projectile body direction with the increase of attack angle; 4. The variance ratio in the outlet has the acute changed with increasing of altitudes clearly, but its corresponding values degrade sharply in the entrance.

  1. Effects of Different Meteorological Standards on Projectile Path

    Directory of Open Access Journals (Sweden)

    R. J. Mukhedkar

    2013-01-01

    Full Text Available Projectile\tpath\tis\tdictated\tby\testimated\tline\tof\tfire.\tLine\tof\tfire\tcan\tbe\testimated\tby\treferring\tRT\tas\twell\tas trajectory model on computer. RT is prepared under ISA/ICAO meteorological standard conditions without wind effect. Meteorological conditions like density, humidity, pressure, wind, temperature affect the path of the trajectory. Meteorological data plays very important role in trajectory prediction. Trajectory is predicted using RT for a particular weapon where ICAO standard met data is used. Ind Std met data is different from ICAO data.\tUse\tof\tInd\tStd\tdata\timproves\tthe\taccuracy\tof\ttrajectory\tprediction\tfor\tIndian\tfield\tdeployment.\tIn\tthis\tpaper, comparative study of effect on projectile path under ICAO, Ind Std and actual Indian prevailing met have been carried out and analyzed. From this analysis, a new model has been established that if actual prevailing met is not available then trajectory prediction can be carried out using Ind Std met data with wind data as per date and time. It predicts trajectory very close to actual. Effect of wind has been studied and found that wind effect is very dominant on projectile path. Study of effect of density also has been carried out in this paper. It is\tobserved\tthat\tInd\tStd\tdensity\tvalues\tare\tmuch\tclose\tto\tactual\tas\tcompared\tto\tICAO.\tTherefore,\tif\tinsufficient\tmet\tis\trecorded\tthen\tInd\tstd\tdensity\tcan\tbe\tused\tto\tfill\tdensity\tvalues\tfor\tthat\tregion.

  2. Initiation of Detonation in Explosives by Impact of Projectiles

    Directory of Open Access Journals (Sweden)

    H.S. Yadav

    2006-04-01

    Full Text Available This paper presents a study of initiation of detonation in explosives by the impact ofprojectiles. The shock wave produced by the impact of projectiles has been considered as thestimulus for initiation of detonation. Three types of projectiles, namely (i flyer plate, (ii flatendedrod, and (iii round-ended rod or a shaped charge jet, have been considered to impact andproduce a shock wave in the explosives. Deriving relations for the parameters of impact-generatedshock wave in the explosives and projectiles, and the sound velocity in the compressed explosives,it has been shown that the difference of kinetic energy of the flyer plate before and after theimpact, which is equal to the total energy of the shock wave in the explosives, leads to criticalenergy criterion for shock initiation of explosives. In this study, the critical criterion has beenused to derive the relations for initiation of explosives by a shaped charge jet, Vj2 D = K0 , whereV j and D denote the velocity and diameter of the jet, and K0 is a constant of the explosive.

  3. Fragmentation of a 500 MeV/nucleon 86Kr beam, investigated at the GSI projectile fragment separator

    International Nuclear Information System (INIS)

    Production cross-sections and longitudinal momentum distributions have been investigated for reactions between a 500 MeV/nucleon 86Kr beam and beryllium, copper and tantalum targets. Fragments in a wide A/Z range were studied at the projectile-fragment separator FRS at GSI. The experimental production cross-sections have been used for testing the predictions obtained from a semi-empirical parameterization, a statistical abrasion model and an intranuclear-cascade model. The present study allows to extrapolate the production cross-sections towards very neutron-rich isotopes such as the doubly magic nucleus 78Ni. For fragments close to the projectile the measured longitudinal momentum distributions agrees qualitatively with a semi-empirical parameterization, which is based on the two-step picture of the fragmentation process. The momentum widths of lighter fragments, however, show deviations from this simple picture. (orig.)

  4. Survivability of copper projectiles during hypervelocity impacts in porous ice: A laboratory investigation of the survivability of projectiles impacting comets or other bodies

    Science.gov (United States)

    McDermott, K. H.; Price, M. C.; Cole, M.; Burchell, M. J.

    2016-04-01

    During hypervelocity impact (>a few km s-1) the resulting cratering and/or disruption of the target body often outweighs interest on the outcome of the projectile material, with the majority of projectiles assumed to be vaporised. However, on Earth, fragments, often metallic, have been recovered from impact sites, meaning that metallic projectile fragments may survive a hypervelocity impact and still exist within the wall, floor and/or ejecta of the impact crater post-impact. The discovery of the remnant impactor composition within the craters of asteroids, planets and comets could provide further information regarding the impact history of a body. Accordingly, we study in the laboratory the survivability of 1 and 2 mm diameter copper projectiles fired onto ice at speeds between 1.00 and 7.05 km s-1. The projectile was recovered intact at speeds up to 1.50 km s-1, with no ductile deformation, but some surface pitting was observed. At 2.39 km s-1, the projectile showed increasing ductile deformation and broke into two parts. Above velocities of 2.60 km s-1 increasing numbers of projectile fragments were identified post impact, with the mean size of the fragments decreasing with increasing impact velocity. The decrease in size also corresponds with an increase in the number of projectile fragments recovered, as with increasing shock pressure the projectile material is more intensely disrupted, producing smaller and more numerous fragments. The damage to the projectile is divided into four classes with increasing speed and shock pressure: (1) minimal damage, (2) ductile deformation, start of break up, (3) increasing fragmentation, and (4) complete fragmentation. The implications of such behaviour is considered for specific examples of impacts of metallic impactors onto Solar System bodies, including LCROSS impacting the Moon, iron meteorites onto Mars and NASA's "Deep Impact" mission where a spacecraft impacted a comet.

  5. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    OpenAIRE

    Aizik F.; Ran E.; Vizel A.; Weiss A.; Paris V.

    2012-01-01

    In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by match...

  6. Study of high-speed interaction processes between fluoropolymer projectiles and aluminum-based targets

    Institute of Scientific and Technical Information of China (English)

    Evgeny A. KHMELNIKOV; Alexey V. STYROV; Konstantin V. SMAGIN; Natalia S. KRAVCHENKO; Valery L. RUDENKO; Vladimir I. FALALEEV; Sergey S. SOKOLOV; Artem V. SVIDINSKY; Natalia F. SVIDINSKAYA

    2015-01-01

    The experimental results and numerical modeling of penetration process of fluoropolymer projectiles in aluminum-based targets are pre-sented. Analysis of mathematical models for interaction of elastoplastic projectile and target without taking additional energy released during interaction of fluoropolymer and aluminum into consideration is carried out. Energy fraction which is spent effectively on the increase in cavity volume is determined. The experimental and calculated results of penetration by combined and inert projectiles are compared.

  7. Mathematical Model to Simulate the Trajectory Elements ofan Artillery Projectile Proof Shot

    OpenAIRE

    K.K. Chand; H.S. Panda

    2007-01-01

    In external ballistics of a conventional spin-stabilised artillery projectile, there are a numberof trajectory models developed for computing trajectory elements having varying degrees ofcomplexity. The present study attempts to propose a single mathematical model, viz., simplifiedpoint-mass/simple particle trajectory model to simulate the trajectory elements of a typical spin-stabilised flat-head artillery projectile proof shot. Due to difficulties in the projectile shape andsize, and the co...

  8. A comparison of finite element analysis to smooth particle hydrodynamics for application to projectile impact on cementitious material

    Science.gov (United States)

    Nordendale, Nikolas A.; Heard, William F.; Sherburn, Jesse A.; Basu, Prodyot K.

    2016-03-01

    The response of structural components of high-strength cementitious (HSC) materials to projectile impact is characterized by high-rate fragmentation resulting from strong compressive shock waves coupled with reflected tensile waves. Accurate modeling of armor panels of such brittle materials under high-velocity projectile impact is a complex problem requiring meticulous experimental characterization of material properties. In a recent paper by the authors, an approach to handle such problems based on a modified Advanced Fundamental Concrete (AFC) constitutive model was developed. In the HSC panels considered in this study, an analogous approach is applied, and the predictions are verified with ballistic impact test data. Traditional Lagrangian finite element analysis (FEA) of these problems tends to introduce errors and suffers from convergence issues resulting from large deformations at free surfaces. Also, FEA cannot properly account for the issues of secondary impact of spalled fragments when multiple armor panels are used. Smoothed particle hydrodynamics (SPH) is considered to be an attractive alternative to resolve these and other issues. However, SPH-based quantitative results have been found to be less accurate than the FEA-based ones when the deformations are not sufficiently large. This paper primarily focuses on a comparison of FEA and SPH models to predict high-velocity projectile impact on single and stacked HSC panels. Results are compared to recent ballistic experiments performed as a part of this research, and conclusions are drawn based on the findings.

  9. Numerical Investigation of Penetration Performance of Non-Ideal Segmented-Rod Projectiles

    Institute of Scientific and Technical Information of China (English)

    ALY S Y; LI Q M

    2008-01-01

    The design of a segmented-rod projectile is often simplified into an ideal one in theoretical analysis for the convenience of modeling of its performance.But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored.AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities, which can be used to guide the optimal design of weaponry segmented-rod projectiles.

  10. Chemical modification of projectile residues and target material in a MEMIN cratering experiment

    Science.gov (United States)

    Ebert, Matthias; Hecht, Lutz; Deutsch, Alexander; Kenkmann, Thomas

    2013-01-01

    In the context of the MEMIN project, a hypervelocity cratering experiment has been performed using a sphere of the iron meteorite Campo del Cielo as projectile accelerated to 4.56 km s-1, and a block of Seeberger sandstone as target material. The ejecta, collected in a newly designed catcher, are represented by (1) weakly deformed, (2) highly deformed, and (3) highly shocked material. The latter shows shock-metamorphic features such as planar deformation features (PDF) in quartz, formation of diaplectic quartz glass, partial melting of the sandstone, and partially molten projectile, mixed mechanically and chemically with target melt. During mixing of projectile and target melts, the Fe of the projectile is preferentially partitioned into target melt to a greater degree than Ni and Co yielding a Fe/Ni that is generally higher than Fe/Ni in the projectile. This fractionation results from the differing siderophile properties, specifically from differences in reactivity of Fe, Ni, and Co with oxygen during projectile-target interaction. Projectile matter was also detected in shocked quartz grains. The average Fe/Ni of quartz with PDF (about 20) and of silica glasses (about 24) are in contrast to the average sandstone ratio (about 422), but resembles the Fe/Ni-ratio of the projectile (about 14). We briefly discuss possible reasons of projectile melting and vaporization in the experiment, in which the calculated maximum shock pressure does not exceed 55 GPa.

  11. Rupture of Human Skin Membrane under Impact of Parabolodial Projectile: Bullet wound Ballistics

    Directory of Open Access Journals (Sweden)

    M. Mukhtar Ali

    1996-10-01

    Full Text Available This paper attempts to study the effect of the impact of a paraboloidal projectile on human shin membrane. The tip of the projectile (i.e., the bullet tip has been considered to be paraboloidal and is made of lead or steel. The threshold velocity i.e., the velocity when the skin membrane is about to rupture has been calculated for human beings of various age groups. The threshold velocity for a paraboloidal projectile of certain dimensions has been found, for all age groups, to be less than that of a spherical projectile under similar conditions.

  12. Effects of Different Meteorological Standards on Projectile Path

    Directory of Open Access Journals (Sweden)

    Rajesh Jayant Mukhedkar

    2013-01-01

    Full Text Available Projectile path is dictated by estimated line of fire. Line of fire can be estimated by referring RT as well as trajectory model on computer. RT is prepared under ISA/ICAO meteorological standard conditions without wind effect. Meteorological conditions like density, humidity, pressure, wind, temperature affect the path of the trajectory. Meteorological data plays very important role in trajectory prediction. Trajectory is predicted using RT for a particular weapon where ICAO standard met data is used. Ind Std met data is different from ICAO data. Use of Ind Std data improves the accuracy of trajectory prediction for Indian field deployment. In this paper, comparative study of effect on projectile path under ICAO, Ind Std and actual Indian prevailing met have been carried out and analyzed. From this analysis, a new model has been established that if actual prevailing met is not available then trajectory prediction can be carried out using Ind Std met data with wind data as perdate and time. It predicts trajectory very close to actual. Effect of wind has been studied and found that wind effect is very dominant on projectile path. Study of effect of density also has been carried out in this paper. It is observed that Ind Std density values are much close to actual as compared to ICAO. Therefore, if insufficient met is recorded then Ind std density can be used to fill density values for that region.Defence Science Journal, 2013, 63(1, pp.101-107, DOI:http://dx.doi.org/10.14429/dsj.63.2641

  13. Mass spectrometric analysis with cluster projectiles and coincidence counting

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B.D.

    1992-01-01

    Methods for maximizing the amount of secondary ion information, per primary projectile, are described. The method is based on time-of-flight mass spectrometry and event-by-event coincidence counting. The information obtained from coincidence counting time-of-flight mass spectrometry includes: (a) surface composition, (b) relative concentrations, and (c) degree of intermolecular mixing. The technique was applied to the study of an important new class of polymers: polymer blends. Secondary ion mass spectrometry, when applied to the analysis of synthetic polymers, induces backbone fragmentation which is characteristic of the homopolymer. The characteristic fingerprint peaks from polystyrene and poly(vinyl methyl ether) were used to identify the presence of these two polymers in a polymer blend. The percent coincidence between the characteristic secondary ions from each component of the blend were used to determine both the relative concentration and the degree of molecular mixing. Results indicate molecular segregation of the two polymers on the film surface. The largest degree of segregation was determined for the phase separated blends. The performance of this technique depends on the desorption efficiency of the primary projectiles. In practice one seeks primary ions which are surface sensitive, have controllable parameters such as size, velocity, and charge state, and generate high secondary ion yields. Focus was placed on the use of keV organic cluster projectiles to meet these criteria. Of interest to this study were C[sub 18] (chrysene), C[sub 24] (coronene), and C[sub 60] (buckminster-fulleren). Results indicate enhanced secondary ion yields for C[sub 60]. For example, when CsI is bombarded with 30 keV C[sub 60], the yields for I[sup [minus

  14. Calculation of forces arising from impacting projectiles upon yielding structures

    International Nuclear Information System (INIS)

    Calculations concerning the impact of airplanes upon nuclear power plant buildings usually imply that the building 'acts' as a rigid target. This assumption is justified for considerations concerning the structural integrity of the building being hit. However, for investigating induced vibrations of components within the structure, this approach might -in general- be too conservative. It is expected, that yielding of the structure during impact reduces the peak values of the loads and changes the temporal behavior of the load function which is obtained for a rigid target. To calculate the changes of the load function which are due to deformations of the structure, Riera's method is extended for the case of a yielding target. In view of the applications of the calculations to the impact of airplanes upon buildings which are constructed to withstand loads of this kind without serious damage and without large deformations, it is possible to simplify the calculations to some extent. That is, the investigations need not take into account in detail the behavior of the target during impact. The calculations are performed with a one-dimensional model for the projectile. The direction of impact is perpendicular to the target surface; direction of impact and projectile axis coincide. The calculations were performed for several initial velocities of the projectiles simulating a fast flying military airplane. Variations of the peak values of the load functions as compared to corresponding values for a rigid target do not exceed about 10%. The overall temporal behavior of the load curves turns out to be not very sensitive to the yielding of the target, though, in some cases displacements in time of the peak positions within a single load curve do arise

  15. Fracture of the humerus caused by a slingshot projectile

    Directory of Open Access Journals (Sweden)

    Dar Tahir Ahmed

    2012-02-01

    Full Text Available 【Abstract】Unconventional and 憂on-lethal?weapons are being used in crowd control regularly nowadays. The use of these arms is not risk-free. The paramilitary forces in 2010 used the old fashioned slingshots for crowd control in Kashmir. A young male suffered from a fracture of the distal humerus due to a marble from a slingshot. He was managed by debridement and plaster splintage. Use of apparently innocuous weapons for crowd control is not without risk, as the projectiles fired from them can achieve high velocities and cause significant damage. Kew words: Humeral fractures; Conducted energy weapon injuries; Firearms

  16. Fracture of the humerus caused by a slingshot projectile

    Institute of Scientific and Technical Information of China (English)

    Tahir Ahmed Dar; Riyaz Ahmed Dar; Mubashir Rashid; Shabir Ahmed Dhar

    2011-01-01

    Unconventional and 'non-lethal' weapons are being used in crowd control regularly nowadays. The use of these arms is not risk-free. The paramilitary forces in 2010 used the old fashioned slingshots for crowd control in Kashmir. A young male suffered from a fracture of the distal humerus due to a marble from a slingshot. He was managed by debridement and plaster splintage. Use of apparently innocuous weapons for crowd control is not without risk, as the projectiles fired from them can achieve high velocities and cause significant damage.

  17. Numerical Simulation of Rigid Projectile's Normally Penetrating into Granite Targets

    Institute of Scientific and Technical Information of China (English)

    张德志; 张向荣; 林俊德; 唐润棣

    2004-01-01

    The process of penetrating into granite was simulated by using program LS-DYNA3D. The granite was represented by the isotropic elastic-plastic model with failure criterion and the projectile was modeled by rigid model. The depth of penetration from simulations is identical with experiments. Penetration deceleration vs striking velocity was acquired at the same time, which can assist in the design of penetration weapons with payload and fuse. Through numerical simulation, that material model is considered with straightforward physical meaning, a few parameters which can be determined easily are more practical for engineering calculation along with experiments.

  18. Aspects of nuclear collectivity studied in projectile Coulomb excitation experiments

    OpenAIRE

    Möller, Thomas

    2014-01-01

    Projectile Coulomb excitation experiments have been performed on the nuclei 130,132Ba, 154Sm, and 194,196Pt. A detailed description of the experiments and the data analysis is given. The results on absolute decay rates of the low-lying collective states of these nuclei allow for a comparison with predictions from different theoretical models of nuclear quadrupole collectivity. For the nucleus 154Sm the data on the decay rates of the states of the first K=0 band support the assignment of this ...

  19. Multiple ionization of neon induced by Li3+ and C3+ projectiles: influence of projectile screening in the ionization and electron capture channels

    Science.gov (United States)

    Ihani, J. S.; Luna, H.; Wolff, W.; Montenegro, E. C.

    2013-06-01

    Neq + (q = 1,2,3,4) ionization and charge exchange cross sections (total electron capture, single electron capture and transfer ionization) in the collisions with Li3+, with energies between 100 and 900 keV amu-1, and C3+, with energies between 250 and 500 keV amu-1 are reported. Bare Li3+ projectiles give a key benchmark to study the role of projectile screening in collisions involving dressed projectile ions, and the measurements have shown a strong screening effect for all n-fold recoil ion charge states in the ionization channel which, unexpectedly, does not appear for transfer ionization.

  20. New projectiles: multicharged metal clusters and biopolymers; De nouveaux projectiles, les agregats metalliques et les biopolymeres multicharges

    Energy Technology Data Exchange (ETDEWEB)

    Della-Negra, S.; Gardes, D.; Le Beyec, Y.; Waast, B.

    1991-12-31

    Metal clusters and molecules are the one mean to realize simultaneous impacts of several atoms on a reduced surface({approx}100A). The interaction characteristics is the non-linearity of energy deposition; the perturbation that the cluster produces, is above than the sum of the perturbation induced by its components, taken separately. The purpose of ORION project is to accelerate these new projectiles at ORSAY Tandem. The considered mass range is from 100 Daltons to 100 000 Daltons and energy range from MeV to GeV.

  1. Electron capture by metastable projectiles on He and Ne

    International Nuclear Information System (INIS)

    Electron capture to n> or =2 levels of F7+ (1s2s) 3S projectiles lead to three-electron ions with an energetically allowed K-Auger decay channel. We have measured the F K-Auger emission spectra for collisions with thin gas targets of He and Ne with sufficiently high resolution to distinguish capture to several of the low-lying n values. The K-Auger production cross sections are reported as a function of the n level into which the electron is captured. The n-level dependence is measured for projectile energies of 6, 9, 12, and 15 MeV and is compared to the Oppenheimer-Brinkman-Kramers OBK model for charge transfer and to a 1/n3 function. The measured K-Auger electron-production cross sections closely follow the 1/n3 function which differs from the predicted OBK n dependence, even though the cross sections for the higher n levels agree with the predicted OBK energy dependence. The effects of cascading upon the calculated n dependence are also studied

  2. Evidence for a large radius of the 11Be projectile

    Science.gov (United States)

    So, W. Y.; Choi, K. S.; Cheoun, Myung-Ki; Kim, K. S.

    2016-05-01

    We investigate ratios of the elastic scattering cross section to Rutherford cross section, PE, and angular distributions of breakup cross section by using an optical model which exploits various long-range dynamic polarization potentials as well as short-range nuclear bare potentials for the 11Be projectile. From these simultaneous analyses, we extract a large radius of a halo projectile from the experimental data for PE and the angular distribution of the breakup cross section of the 11Be + 64Zn and 11 + 120Sn systems. It results from the fact that a large radius for the long-range nuclear potential is more reasonable for properly explaining these data simultaneously. The extracted reduced interaction radius turns out to be r0=3.18 ˜3.61 fm for 11Be nucleus, which is larger than the conventional value of r0=1.1 ˜1.5 fm used in the standard radius form R =r0A1 /3 . Furthermore, the larger radius as well as the normalization constant N is shown to be important for understanding Coulomb dipole strength distribution.

  3. Projectile charge state dependent sputtering of solid surfaces

    CERN Document Server

    Hayderer, G

    2000-01-01

    dependence on the ion kinetic energy. This new type of potential sputtering not only requires electronic excitation of the target material, but also the formation of a collision cascade within the target in order to initiate the sputtering process and has therefore been termed kinetically assisted potential sputtering. In order to study defects induced by potential sputtering on the atomic scale we performed measurements of multiply charged Ar ion irradiated HOPG (highly oriented pyrolitic graphite) samples with scanning tunneling microscopy (STM). The only surface defects found in the STM images are protrusions. The mean diameter of the defects increases with projectile charge state while the height of the protrusions stays roughly the same indicating a possible pre-equilibrium effect of the stopping of slow multiply charged projectiles in HOPG. Total sputter yields for impact of slow singly and multiply charged ions on metal- (Au), oxide- (Al2O3, MgO) and alkali-halide surfaces (LiF) have been measured as a...

  4. Reaction dynamics of {sup 34-38}Mg projectile with carbon target using Glauber model

    Energy Technology Data Exchange (ETDEWEB)

    Shama, Mahesh K., E-mail: maheshphy82@gmail.com [School of Physics and Material Sciences, Thapar University Patiala-147004 (India); Department of Applied Sciences, Chandigarh Engineering College, Landran Mohali-140307 (India); Panda, R. N. [Department of Physics, ITER, Shiksha O Anusandhan University, Bhubaneswar-751030 (India); Sharma, Manoj K. [School of Physics and Material Sciences, Thapar University Patiala-147004 (India); Patra, S. K. [Institute of Physics, Sachivalaya marg Bhubneswar-751005 (India)

    2015-08-28

    We have studied nuclear reaction cross-sections for {sup 34-38}Mg isotopes as projectile with {sup 12}C target at projectile energy 240AMeV using Glauber model with the conjunction of densities from relativistic mean filed formalism. We found good agreement with the available experimental data. The halo status of {sup 37}Mg is also investigated.

  5. Light-particle multiplicity accompanying projectile breakup at 20 MeV/A

    International Nuclear Information System (INIS)

    A large-solid-angle array has been used to determine the multiplicity of Z = 1 and Z = 2 particles accompanying projectile breakup into two fragments each with 5 ≤ Z ≤ 8. The charge balance obtained shows that projectile breakup is not associated with an unusual charge transfer to the target. 13 refs., 1 fig

  6. Treatment of Ion-Atom Collisions Using a Partial-Wave Expansion of the Projectile Wavefunction

    Science.gov (United States)

    Wong, T. G.; Foster, M.; Colgan, J.; Madison, D. H.

    2009-01-01

    We present calculations of ion-atom collisions using a partial-wave expansion of the projectile wavefunction. Most calculations of ion-atom collisions have typically used classical or plane-wave approximations for the projectile wavefunction, since partial-wave expansions are expected to require prohibitively large numbers of terms to converge…

  7. Deformation and Melting of Iron-Rich Projectiles in Hypervelocity MEMIN Cratering Experiments

    Science.gov (United States)

    Kenkmann, T.; Ebert, M.; Trullenque, G.; Deutsch, A.; Hecht, L.; Salge, T.; Schäfer, F.; Thoma, K.

    2013-09-01

    We conducted 23-54 kJ impact experiments using projectiles composed of steel and iron meteorite Campo del Cielo to study the structural changes that occur upon impact in these projectiles. Extensive melting is largely the result of plastic deformation.

  8. Comment on "The motion of an arbitrarily rotating spherical projectile and its application to ball games"

    DEFF Research Database (Denmark)

    Jensen, Jens Højgaard

    2014-01-01

    independent of the Reynolds number and proportional to the square of the projectile's velocity. In this paper, by dimensional analysis, the latter assumption is shown to be incorrect for forces dependent on the angular velocity of the projectile, e.g. the lift force....

  9. Instantaneous charge state of Uranium projectiles in fully ionized plasmas from energy loss experiments

    CERN Document Server

    Morales, Roberto; Casas, David

    2016-01-01

    The instantaneous charge state of uranium ions traveling through a fully ionized hydrogen plasma has been theoretically studied and compared with one of the first energy loss experiments in plasmas, carried out at GSI-Darmstadt by Hoffmann \\textit{et al.} in the 90's. For this purpose, two different methods to estimate the instantaneous charge state of the projectile have been employed: (1) rate equations using ionization and recombination cross sections, and (2) equilibrium charge state formulas for plasmas. Also, the equilibrium charge state has been obtained using these ionization and recombination cross sections, and compared with the former equilibrium formulas. The equilibrium charge state of projectiles in plasmas is not always reached, it depends mainly on the projectile velocity and the plasma density. Therefore, a non-equilibrium or an instantaneous description of the projectile charge is necessary. The charge state of projectile ions cannot be measured, except after exiting the target, and experime...

  10. Finite Element Modeling of Transient Temperatures in a Small-Caliber Projectile

    Directory of Open Access Journals (Sweden)

    M. B. Thomas

    2010-01-01

    Full Text Available Problem statement: Future generations of intelligent munitions will use Microelectromechanical Systems (MEMS for guidance, fuzing logic and assessment of the battlefield environment. The temperatures fund in a gun system, however, are sufficient to damage some materials used in the fabrication of MEMS. The motivation of this study is to model the dynamic temperature distribution in a typical small-caliber projectile. Approach: An axisymmetric finite-element model of a projectile is developed to simulate temperatures through internal ballistics (the projectile is in the gun barrel and external ballistics (the projectile travels in a free trajectory towards the target. Accuracy of the simulation is confirmed through comparison to analytical models and to payloads attached to experimental projectiles. In the simulation, the exact values for some boundary conditions are unknown and/or unknowable. A sensitivity analysis determines the effect of these uncertain parameters. Results: The simulation shows that friction at the projectile-gun barrel interface is primarily responsible for elevated temperatures in a gun system. Other factors have much smaller effects. The short duration of the internal ballistics prevents the frictional heat from diffusing into the bulk of the projectile. As a result, the projectile has a shallow, high-temperature zone at its bearing surface as it leaves the gun barrel. During external ballistics, this heat will diffuse through the projectile, but most of the projectile experiences temperatures of 56°C or lower. Simulation shows that the polymer package around a MEMS device will further attenuate heat flow, limiting temperatures in the device to less than 30°C. Conclusion: The finite element model demonstrates that a MEMS device may be engineered to survive temperatures expected in the ballistic environment.

  11. Projectile dependency of radioactivities of spallation products induced in copper

    Energy Technology Data Exchange (ETDEWEB)

    Yashima, Hiroshi; Sugita, Hiroshi; Nakamura, Takashi; Shiomi, Tomoyuki [Tohoku Univ., Department of Quantum Science and Energy Engineering, Sendai, Miyagi (Japan); Uwamino, Yoshitomo; Ito, Sachiko [Institute of Physical and Chemical Research, Wako, Saitama (Japan); Fukumura, Akifumi [National Institute of Radiological Sciences, Chiba (Japan)

    2001-03-01

    The reaction cross-sections of spallation products in a Cu target by 230 MeV/nucleon Ne, C, He, p and 100 MeV/nucleon Ne, C ions were obtained. Irradiation experiments were performed at HIMAC (Heavy Ion Medical Accelerator in Chiba), National Institute of Radiological Sciences. Gamma-ray spectra from activation samples were measured with an HPGe detector. >From the gamma-ray spectra, we obtained the variation of reaction cross sections of Cl-38, Cr-49, Mn-55, Cu-60, Cu-61 and Co-62m in Cu sample with Cu target thickness and mass-yield distribution of nuclides in Cu sample on the surface of Cu target. The results showed that the dependence of the cross-sections to the projectile mass varies with the mass number difference between Cu and produced nuclide. (author)

  12. Expert Systems Aimed at General Design of Projectiles

    Institute of Scientific and Technical Information of China (English)

    YUAN Zhi-hua; HOU Ni-na; HU Yu-hui

    2007-01-01

    Expert systems aimed at the general design of projectiles can implement a series of intelligent designs, such as the design of HE shell, the scheme expounded and proved, the emulation analysis and calculation, etc. Aiming at the product design feature, the expert system adopts the object-oriented knowledge representation and all kinds of inference control engines to describe and reason the relevant knowledge regarding the product through the microcomputer. It embodies the foundation of emulation analysis and simulated manufacturing of the shell. It makes use of the method that knowledge expression is combined with condition of inference to carry out the overall design and emulation and reference.The paper gives the ways through which the functions can be achieved, gives the modularization of reference and the design methods of systematization, puts forward the method of knowledge expression and working interface, and supplies a platform for similar products of the shell category that can be quickly designed.

  13. Aerodynamic Jump: A Short Range View for Long Rod Projectiles

    Directory of Open Access Journals (Sweden)

    Mark Bundy

    2001-01-01

    Full Text Available It is shown that aerodynamic jump for a nonspinning kinetic energy penetrator is not – as conventional definitions may infer – a discontinuous change in the direction of motion at the origin of free flight, nor is it the converse, a cumulative redirection over a domain of infinite extent. Rather, with the aid of an alternative kinematical definition, it is shown that aerodynamic jump for such a projectile is a localized redirection of the center-of-gravity motion, caused by the force of lift due to yaw over the relatively short region from entry into free flight until the yaw reaches its first maximum. A rigorous proof of this statement is provided, but the primary objective of this paper is to provide answers to the questions: what is aerodynamic jump, what does it mean, and what aspects of the flight trajectory does it refer to, or account for.

  14. A Method for Guiding a Salvo of guided Projectiles to a Target, a System and a Computer Program Product

    NARCIS (Netherlands)

    Ruizenaar, M.G.A.

    2011-01-01

    The invention relates to a method of guiding a salvo of guided projectiles to a target. The method comprises the steps of generating a beam defining a common reference coordinate system, determining the position of each projectile relative to the beam, and providing to each projectile: position info

  15. A distorted-wave Born-approximation theory of heavy-ion induced projectile break-up reactions

    International Nuclear Information System (INIS)

    A distorted-wave Born-approximation (DWBA) formalism is developed to describe the 'elastic' and 'inelastic' break-up of the projectile in the heavy ion induced reactions. Using a 'local momentum approximation' and the surface localization property of these reactions expressions for the DWBA transition amplitude are derived. One of the attractive features of the present formulation is the fact that the readial integrals involved in it are the same as those contained in the transition amplitude evaluated with a zero range approximation. The validity of the approximations used in our derivations has been tested and it is shown that these approximations are well fulfilled. (orig.)

  16. Breakup conditions of projectile spectators from dynamical observables

    Energy Technology Data Exchange (ETDEWEB)

    Begemann-Blaich, M.; Lindenstruth, V.; Pochodzalla, J. [and others

    1998-03-01

    Momenta and masses of heavy projectile fragments (Z {>=} 8), produced in collisions of {sup 197}Au with C, Al, Cu and Pb targets at E/A=600 MeV, were determined with the ALADIN magnetic spectrometer at SIS. Using these informations, an analysis of kinematic correlations between the two and three heaviest projectile fragments in their rest frame was performed. The sensitivity of these correlations to the conditions at breakup was verified within the schematic SOS-model. For a quantitative investigation, the data were compared to calculations with statistical multifragmentation models and to classical three-body calculations. With classical trajectory calculations, where the charges and masses of the fragments are taken from a Monte Carlo sampling of the experimental events, the dynamical observables can be reproduced. The deduced breakup parameters, however, differ considerably from those assumed in the statistical multifragmentation models which describe the charge correlations. If, on the other hand, the analysis of kinematic and charge correlations is performed for events with two and three heavy fragments produced by statistical multifragmentation codes, a good agreement with the data is found with the exception that the fluctuation widths of the intrinsic fragment energies are significantly underestimated. A new version of the multifragmentation code MCFRAG was therefore used to investigate the potential role of angular momentum at the breakup stage. If a mean angular momentum of 0.75 {Dirac_h}/nucleon is added to the system, the energy fluctuations can be reproduced, but at the same time the charge partitions are modified and deviate from the data. (orig.)

  17. Breakup conditions of projectile spectators from dynamical observables

    International Nuclear Information System (INIS)

    Momenta and masses of heavy projectile fragments (Z ≥ 8), produced in collisions of 197Au with C, Al, Cu and Pb targets at E/A=600 MeV, were determined with the ALADIN magnetic spectrometer at SIS. Using these informations, an analysis of kinematic correlations between the two and three heaviest projectile fragments in their rest frame was performed. The sensitivity of these correlations to the conditions at breakup was verified within the schematic SOS-model. For a quantitative investigation, the data were compared to calculations with statistical multifragmentation models and to classical three-body calculations. With classical trajectory calculations, where the charges and masses of the fragments are taken from a Monte Carlo sampling of the experimental events, the dynamical observables can be reproduced. The deduced breakup parameters, however, differ considerably from those assumed in the statistical multifragmentation models which describe the charge correlations. If, on the other hand, the analysis of kinematic and charge correlations is performed for events with two and three heavy fragments produced by statistical multifragmentation codes, a good agreement with the data is found with the exception that the fluctuation widths of the intrinsic fragment energies are significantly underestimated. A new version of the multifragmentation code MCFRAG was therefore used to investigate the potential role of angular momentum at the breakup stage. If a mean angular momentum of 0.75 ℎ/nucleon is added to the system, the energy fluctuations can be reproduced, but at the same time the charge partitions are modified and deviate from the data. (orig.)

  18. Investigations of nuclear projectile break-up reactions

    International Nuclear Information System (INIS)

    The cross sections for radiative capture of α-particles, deuterons and protons by light nuclei at very low relative energies are of particular importance for the understanding of the nucleosynthesis of chemical elements and for determining the relative elemental abundances in stellar burning processes at various astrophysical sites. As example we quote the reactions α+d → 6Li+γ, α+3He → 7Be+γ, or α+12C → 16O+γ. As an alternative to the direct experimental study of these processes we consider the inverse process, the photodisintegration, by means of the virtual photons provided by a nuclear Coulomb field: Z+a → Z+b+c. The radiative capture process b+c → a+γ is related to the inverse process, the photodisintegration γ+a → b+c by the detailed balance theorem. Except for the extreme case very close to the threshold the phase space favours the photodisintegration cross section as compared to the radiative capture. The Coulomb dissociation cross section proves to be enhanced due to the large virtual photon number, seen by the passing projectile, and the kinematics of the process leads to particular advantages for studies of the interaction of the two break-up fragments at small relative energies Ebc. The conditions of dedicated experimental investigations are discussed and demonstrated by recent experimental and theoretical studies of the break-up of 156 MeV 6Li projectiles. In addition, a brief review about general features of break-up processes of light ions in the field of atomic nuclei is given. (orig.)

  19. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Science.gov (United States)

    Kruszka, L.; Magier, M.

    2012-08-01

    The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity) in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it's particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot) and tungsten alloy (penetrator) are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ṡ 104s-1 (for aluminium alloy) and 6 ṡ 103s-1 (for tungsten alloy).

  20. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Directory of Open Access Journals (Sweden)

    Magier M.

    2012-08-01

    Full Text Available The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it’s particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot and tungsten alloy (penetrator are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ⋅ 104s−1 (for aluminium alloy and 6 ⋅ 103s−1 (for tungsten alloy.

  1. The influence of aerodynamic coefficients on the elements of classic projectile paths

    Directory of Open Access Journals (Sweden)

    Damir D. Jerković

    2011-04-01

    Full Text Available The article deals with the results of the research on the influence of aerodynamic coefficient values on the trajectory elements and the stability parameters of classic axisymmetric projectiles. It presents the characteristic functions of aerodynamic coefficients with regard to aerodynamic parameters and the projectile body shape. The trajectory elements of the model of classic axisymmetric projectiles and the analyses of their changes were presented with respect to the aerodynamic coefficient values. Introduction Classic axisymmetric projectiles fly through atmosphere using muzzle velocity as initial energy resource, so the aerodynamic force and moment have the most significant influence on the motion of projectiles. The aerodynamic force and moment components represented as aerodynamic coefficients depend on motion velocity i. e. flow velocity, the flow features produced by projectile shape and position in the flow, and angular velocity (rate of the body. The functional dependence of aerodynamic coefficients on certain influential parameters, such as angle of attack and angular velocity components is expressed by the derivative of aerodynamic coefficients. The determination of aerodynamic coefficients and derivatives enables complete definition of the aerodynamic force and moment acting on the classic projectile. The projectile motion problem is considered in relation to defining the projectile stability parameters and the conditions under which the stability occurs. The comparative analyses of aerodynamic coefficient values obtained by numerical methods, semi empirical calculations and experimental research give preliminary evaluation of the quality of the determined values. The flight simulation of the motion of a classic axisymetric projectile, which has the shape defined by the aerodynamic coefficient values, enables the comparative analyses of the trajectory elements and stability characteristics. The model of the classic projectile

  2. High-speed Imaging of Global Surface Temperature Distributions on Hypersonic Ballistic-Range Projectiles

    Science.gov (United States)

    Wilder, Michael C.; Reda, Daniel C.

    2004-01-01

    The NASA-Ames ballistic range provides a unique capability for aerothermodynamic testing of configurations in hypersonic, real-gas, free-flight environments. The facility can closely simulate conditions at any point along practically any trajectory of interest experienced by a spacecraft entering an atmosphere. Sub-scale models of blunt atmospheric entry vehicles are accelerated by a two-stage light-gas gun to speeds as high as 20 times the speed of sound to fly ballistic trajectories through an 24 m long vacuum-rated test section. The test-section pressure (effective altitude), the launch velocity of the model (flight Mach number), and the test-section working gas (planetary atmosphere) are independently variable. The model travels at hypersonic speeds through a quiescent test gas, creating a strong bow-shock wave and real-gas effects that closely match conditions achieved during actual atmospheric entry. The challenge with ballistic range experiments is to obtain quantitative surface measurements from a model traveling at hypersonic speeds. The models are relatively small (less than 3.8 cm in diameter), which limits the spatial resolution possible with surface mounted sensors. Furthermore, since the model is in flight, surface-mounted sensors require some form of on-board telemetry, which must survive the massive acceleration loads experienced during launch (up to 500,000 gravities). Finally, the model and any on-board instrumentation will be destroyed at the terminal wall of the range. For these reasons, optical measurement techniques are the most practical means of acquiring data. High-speed thermal imaging has been employed in the Ames ballistic range to measure global surface temperature distributions and to visualize the onset of transition to turbulent-flow on the forward regions of hypersonic blunt bodies. Both visible wavelength and infrared high-speed cameras are in use. The visible wavelength cameras are intensified CCD imagers capable of integration

  3. Geochemical processes between steel projectiles and silica-rich targets in hypervelocity impact experiments

    Science.gov (United States)

    Ebert, Matthias; Hecht, Lutz; Deutsch, Alexander; Kenkmann, Thomas; Wirth, Richard; Berndt, Jasper

    2014-05-01

    The possibility of fractionation processes between projectile and target matter is critical with regard to the classification of the impactor type from geochemical analysis of impactites from natural craters. Here we present results of five hypervelocity MEMIN impact experiments (Poelchau et al., 2013) using the Cr-V-Co-Mo-W-rich steel D290-1 as projectile and two different silica-rich lithologies (Seeberger sandstone and Taunus quartzite) as target materials. Our study is focused on geochemical target-projectile interaction occurring in highly shocked and projectile-rich ejecta fragments. In all of the investigated impact experiments, whether sandstone or quartzite targets, the ejecta fragments show (i) shock-metamorphic features e.g., planar-deformation features (PDF) and the formation of silica glasses, (ii) partially melting of projectile and target, and (iii) significant mechanical and chemical mixing of the target rock with projectile material. The silica-rich target melts are strongly enriched in the "projectile tracer elements" Cr, V, and Fe, but have just minor enrichments of Co, W, and Mo. Inter-element ratios of these tracer elements within the contaminated target melts differ strongly from the original ratios in the steel. The fractionation results from differences in the reactivity of the respective elements with oxygen during interaction of the metal melt with silicate melt. Our results indicate that the principles of projectile-target interaction and associated fractionation do not depend on impact energies (at least for the selected experimental conditions) and water-saturation of the target. Partitioning of projectile tracer elements into the silicate target melt is much more enhanced in experiments with a non-porous quartzite target compared with the porous sandstone target. This is mainly the result of higher impact pressures, consequently higher temperatures and longer reaction times at high temperatures in the experiments with quartzite as

  4. Rupture of Human Skin Membrane under Impact of Parabolodial Projectile: Bullet wound Ballistics

    OpenAIRE

    M. Mukhtar Ali; Vijay Paul Singh; GH. Nabi Parrey

    1996-01-01

    This paper attempts to study the effect of the impact of a paraboloidal projectile on human shin membrane. The tip of the projectile (i.e., the bullet tip) has been considered to be paraboloidal and is made of lead or steel. The threshold velocity i.e., the velocity when the skin membrane is about to rupture has been calculated for human beings of various age groups. The threshold velocity for a paraboloidal projectile of certain dimensions has been found, for all age groups, to be les...

  5. The Paradigm of Projectile Motion and its Consequences for Special Relativity. Making Sense of Physics

    CERN Document Server

    Klevgard, Paul A

    2015-01-01

    The classical (Newtonian) concept of projectile motion underwent a series of seemingly minor changes and adjustments between the discovery of the quantum (Planck, 1900) and the early codification of quantum theory (Dirac, 1928). The goal of physicists in this period was to keep change to a minimum and preserve as much as possible of the traditional projectile paradigm (TPP). These adjustments were successful in masking an all-out projectile paradigm crisis, but they have left us with a conceptual muddle. This has been especially deleterious for special relativity and our understanding of space contraction and time dilation.

  6. Projectile motion in real-life situation: Kinematics of basketball shooting

    Science.gov (United States)

    Changjan, A.; Mueanploy, W.

    2015-06-01

    Basketball shooting is a basic practice for players. The path of the ball from the players to the hoop is projectile motion. For undergraduate introductory physics courses student must be taught about projectile motion. Basketball shooting can be used as a case study for learning projectile motion from real-life situation. In this research, we discuss the relationship between optimal angle, minimum initial velocity and the height of the ball before the player shoots the ball for basketball shooting problem analytically. We found that the value of optimal angle and minimum initial velocity decreases with increasing the height of the ball before the player shoots the ball.

  7. Acceleration of small, light projectiles (including hydrogen isotopes) to high speeds using a two-stage light gas gun

    International Nuclear Information System (INIS)

    Small, light projectiles have been accelerated to high speeds using a two-stage light gas gun at Oak Ridge National Laboratory. With 35-mg plastic projectiles (4 mm in diameter), speeds of up to 4.5 km/s have been recorded. The ''pipe gun'' technique for freezing hydrogen isotopes in situ in the gun barrel has been used to accelerate deuterium pellets (nominal diameter of 4 mm) to velocities of up to 2.85 km/s. The primary application of this technology is for plasma fueling of fusion devices via pellet injection of hydrogen isotopes. Conventional pellet injectors are limited to pellet speeds in the range 1-2 km/s. Higher velocities are desirable for plasma fueling applications, and the two-stage pneumatic technique offers performance in a higher velocity regime. However, experimental results indicate that the use of sabots to encase the cryogenic pellets and protect them for the high peak pressures will be required to reliably attain intact pellets at speeds of ∼3 km/s or greater. In some limited tests, lithium hydride pellets were accelerated to speeds of up to 4.2 km/s. Also, repetitive operation of the two-stage gun (four plastic pellets fired at ∼0.5 Hz) was demonstrated for the first time in preliminary tests. The equipment and operation are described, and experimental results and some comparisons with a theoretical model are presented. 17 refs., 6 figs., 2 tabs

  8. Radiation hardness investigation of avalanche photodiodes for the Projectile Spectator Detector readout at the Compressed Baryonic Matter experiment

    International Nuclear Information System (INIS)

    In this paper, we discuss results of avalanche photodiodes radiation tests for Projectile Spectator Detector at future Compressed Baryonic Matter experiment. The tests were carried out in Nuclear Physics Institute of ASCR in Řež using the cyclotron facility. Secondary neutron beam was used for irradiation because the main radiation damage in the Projectile Spectator Detector is caused by neutrons. Two types of the avalanche photodiodes from Zecotek and Ketek manufacturers were investigated. Special attention was given to the noise investigation and self-annealing after the irradiation. We have irradiated two Ketek PM3375 diodes with equivalent dose for 1 MeV neutrons equal to 2.5±0.2×1012 n/cm2, and single Zecotek MAPD-3N diode with equivalent dose for 1 MeV neutrons equal to 3.4±0.2×1012 n/cm2. All the types of the diodes have shown an increasing level of the noise after the irradiation. From that we can conclude that those avalanche photodiodes are not able to detect single photons anymore due to high noise levels

  9. RESEARCH ON THE BASE CAVITY OF A SUB-LAUNCHED PROJECTILE

    Institute of Scientific and Technical Information of China (English)

    CAO Jia-yi; LU Chuan-jing; CHEN Ying; CHEN Xin; LI Jie

    2012-01-01

    The finite volume method based on a multiphase model is adopted to solve the Reynolds-Averaged Navier-Stokes (RANS)equations,which takes into account the effects of fluid compressibility,viscosity,gravity,medium mixture and energy transfer of water and combustion gas.The program Fluent User Define Function (UDF) module combined with the dynamic mesh method is employed to simulate the coupling flow field of combustion gas,water field and trajectory of projectile.The results show that the volume of gas cavity at the bottom of projectile and tail pressure will fluctuate after bottom of the projectile leaving the launch tube.The cause of the fluctuation is analyzed and its effects on the trajectory of projectile are presented.The numerical and experimental results agree well with each other.

  10. A New Simple Model for the Mushrooming Deformation of Projectile Impacting on A Deformable Target

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoqing; Yang Guitong

    2004-01-01

    Based on Taylor's model and Hawkyard's model, a new simple model for the mushrooming deformation of projectile impacting on a deformable target is installed considering the penetration of the projectile to the deformable target. In the model, the following time-dependent variables are involved in: the extent and the particle velocity in the rigid zone; the extent, the cross-section area and the particle velocity in plastic zone; the velocity and depth of the penetrating of projectile to the target. Solving the set of equations, analytic solution is given. The profiles of deformed projectile and shape parameters for different initial impact velocities are shown. The duration time of deformation increases with increasing the impact velocity. The analytical results by using this model are coincident with experimental result.

  11. MEMIN Project: The Search for Suitable Projectile Material in Meso-Scale Hypervelocity Cratering Experiments

    Science.gov (United States)

    Domke, I.; Deutsch, A.; Hecht, L.; Kenkmann, T.

    2010-03-01

    We report textural and geochemical data (EMP, LA-ICP-MS) for different types of steel and the iron meteorites Arispe (IC) and Campo del Cielo (IAB) that are evaluated as projectile materials in hypervelocity cratering experiments .

  12. Development of odd-Z-projectile reactions for transactinide element synthesis

    International Nuclear Information System (INIS)

    The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile energies in the latter reaction were too high for optimum production of the 1n product. At the highest projectile energy of 268.0 MeV in the target center, two decay

  13. Development of odd-Z-projectile reactions for transactinide element synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Folden III, Charles Marvin

    2004-11-04

    The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile energies in the latter reaction were too high for optimum production of the 1n product. At the highest projectile energy of 268.0 MeV in the target center, two decay

  14. Study of Hypervelocity Projectile Impact on Thick Metal Plates

    Directory of Open Access Journals (Sweden)

    Shawoon K. Roy

    2016-01-01

    Full Text Available Hypervelocity impacts generate extreme pressure and shock waves in impacted targets that undergo severe localized deformation within a few microseconds. These impact experiments pose unique challenges in terms of obtaining accurate measurements. Similarly, simulating these experiments is not straightforward. This study proposed an approach to experimentally measure the velocity of the back surface of an A36 steel plate impacted by a projectile. All experiments used a combination of a two-stage light-gas gun and the photonic Doppler velocimetry (PDV technique. The experimental data were used to benchmark and verify computational studies. Two different finite-element methods were used to simulate the experiments: Lagrangian-based smooth particle hydrodynamics (SPH and Eulerian-based hydrocode. Both codes used the Johnson-Cook material model and the Mie-Grüneisen equation of state. Experiments and simulations were compared based on the physical damage area and the back surface velocity. The results of this study showed that the proposed simulation approaches could be used to reduce the need for expensive experiments.

  15. Histologic Analysis of Pig Muscle Tissue after Wounding with a High-Velocity Projectile - Preliminary Report

    OpenAIRE

    Korać, Želimir; Crnica, Suad; Demarin, Vida

    2006-01-01

    Terminal ballistics of high-velocity projectiles is focused primarily on evaluation of the effects of penetrating projectiles on tissue simulants, but there is always a question of their similarity with live tissue. Ethical problems related to using live animals in terminal ballistic researches have resulted in a reduced number of these experiments. The aim of this study was to analyze histologic effects of high-velocity missiles in swine muscle tissue. The hypothesis was that a penetrating p...

  16. Numerical Simulation on Ceramic/Metal Armours Impacted by Deformable Projectile

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoqing; Yao Xiaohu; Yang Guitong

    2004-01-01

    Numerical simulation for the dynamic response of ceramic/metal armours impacted by deformable projectile is carried out with LS-DYNA3D.The simulated penetration processes are shown. The mushrooming of the projectile is displayed. A distinct conoid shaped zone of fragmented ceramic is observed. A significant bending of the backing plate is revealed. Simulation results match fairly well with the experimental values and the theoretical analysis results. The accuracy of the numerical simulation is validated.

  17. Finite Element Modeling of Transient Temperatures in a Small-Caliber Projectile

    OpenAIRE

    M. B. Thomas; Leon Dozier

    2010-01-01

    Problem statement: Future generations of intelligent munitions will use Microelectromechanical Systems (MEMS) for guidance, fuzing logic and assessment of the battlefield environment. The temperatures fund in a gun system, however, are sufficient to damage some materials used in the fabrication of MEMS. The motivation of this study is to model the dynamic temperature distribution in a typical small-caliber projectile. Approach: An axisymmetric finite-element model of a projectile is developed...

  18. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    Science.gov (United States)

    Paris, V.; Weiss, A.; Vizel, A.; Ran, E.; Aizik, F.

    2012-08-01

    In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH) armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile's core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

  19. NUMERICAL SIMULATION OF THREE DIMENSIONAL INTERACTING TURBULENCE FLOW FIELD OVER PROJECTILE WITH LATERAL JETS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to study complicated interacting flow field over projectile with lateral jets. External interacting turbulence flow over projectile with lateral jets was numerically simulated firstly in supersonic speed and zero attack angle. The three dimensional Reynolds-averaged NavierStokes equations and implicit finite volume TVD scheme grid of single zone including projectile base was produced by algebraic arithmetic. Body-fitted grid was generated for the lateral nozzle exit successfully so that the nozzle exit can be simulated more accurately. The high Reynolds number two-equation κ-ε turbulence models were used.The main features of the complex flow are captured. The two kinds of flow field over projectile with and without lateral jets are compared from shock structure, pressure of body and base, etc. It shows that lateral jets not only can provide push force, but also change aerodynamics characteristic of projectile significantly. The results are very important for the study of projectile with lateral rocket boosters.``

  20. Fairly direct hit. Advances in imaging of shotgun projectiles in MRI

    Energy Technology Data Exchange (ETDEWEB)

    Eggert, Sebastian [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); University of Zurich, Institute of Forensic Medicine, Zurich (Switzerland); Kubik-Huch, Rahel A.; Peters, Alexander [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); Klarhoefer, Markus [Siemens Healthcare, Zurich (Switzerland); Bolliger, Stephan A.; Thali, Michael J. [University of Zurich, Institute of Forensic Medicine, Zurich (Switzerland); Anderson, Suzanne [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); University of Notre Dame Australia, Radiology, Sydney School of Medicine, Sydney, NSW (Australia); Froehlich, Johannes M. [Federal Institute of Technology, Pharmaceutical Sciences, Zurich (Switzerland)

    2015-09-15

    To investigate the magnetic properties of different types of projectiles and qualify the metal artefact reduction technique for diagnostic and/or forensic MRI. Ten different projectiles embedded in ordnance gelatine blocks underwent an in vitro 1.5-T MR study with seven sequences including a recently developed metal artefact reduction sequence (Advanced WARP) combining VAT (view-angle-tilting) and SEMAC (slice-encoding metal-artefact-correction). Resulting image quality (five-point scale: 1=best; 5=worst) was scored. Quantifiable magnetic characteristics were correlated with qualitative rating of the MR sequences and torque dislodgment. Metal artefact reduction sequence (median: 2.5) significantly (p < 0.001) improves depiction of projectiles in comparison to all other MR pulse sequences (median: 4.75). Images from diamagnetic composed bullets (median: 2) are much less disturbed compared to magnetic attracted ones (median: 5). Correlation (0.623) between deflection angle measurement (ferromagnetic mean 84.2 ; paramagnetic 62 ; diamagnetic mean 0 ) and median qualitative image quality was highly significant (p = 0.027). Torque dislodgement was distinct for elongated magnetic attracted projectiles. Significant improvement of MR imaging of projectiles using metal artefact reduction techniques has important implications for diagnostic/forensic work-up. The correlations between magnetic attraction force, deflection-angle results and image properties demonstrate that the MR safety of projectiles can be estimated with one of these methods. (orig.)

  1. Fairly direct hit. Advances in imaging of shotgun projectiles in MRI

    International Nuclear Information System (INIS)

    To investigate the magnetic properties of different types of projectiles and qualify the metal artefact reduction technique for diagnostic and/or forensic MRI. Ten different projectiles embedded in ordnance gelatine blocks underwent an in vitro 1.5-T MR study with seven sequences including a recently developed metal artefact reduction sequence (Advanced WARP) combining VAT (view-angle-tilting) and SEMAC (slice-encoding metal-artefact-correction). Resulting image quality (five-point scale: 1=best; 5=worst) was scored. Quantifiable magnetic characteristics were correlated with qualitative rating of the MR sequences and torque dislodgment. Metal artefact reduction sequence (median: 2.5) significantly (p < 0.001) improves depiction of projectiles in comparison to all other MR pulse sequences (median: 4.75). Images from diamagnetic composed bullets (median: 2) are much less disturbed compared to magnetic attracted ones (median: 5). Correlation (0.623) between deflection angle measurement (ferromagnetic mean 84.2 ; paramagnetic 62 ; diamagnetic mean 0 ) and median qualitative image quality was highly significant (p = 0.027). Torque dislodgement was distinct for elongated magnetic attracted projectiles. Significant improvement of MR imaging of projectiles using metal artefact reduction techniques has important implications for diagnostic/forensic work-up. The correlations between magnetic attraction force, deflection-angle results and image properties demonstrate that the MR safety of projectiles can be estimated with one of these methods. (orig.)

  2. Locus Model for the Pellet's Shiver of Smoke Projectile%烟幕弹的发烟剂碎块轨迹模型

    Institute of Scientific and Technical Information of China (English)

    朱晨光; 潘功配; 陈敬业; 杨志强

    2006-01-01

    利用飞散物在运动过程中所受到的空气阻力和重力建立飞散物运动方程,用高速摄影仪拍摄了烟幕爆炸成烟过程,并用实验结果求出了相关系数,校正了模型.结果发现空气阻力对烟幕成型有明显的影响.%The locus equation for the pellet's shiver of smoke projectile was established by using the air friction and the gravitation, and the solving process of equation was presented. The exploding process of smoke projectile was shot by a high speed camera. Test data were used to obtain related coefficients, and the mathematical model was modified further.The results illustrate that air friction effect on the flying locus of shiver is significant.

  3. Behavior of steel fiber high strength concrete under impact of projectiles

    Directory of Open Access Journals (Sweden)

    Cánovas, M. F.

    2012-09-01

    Full Text Available This paper presents the results of the investigation carried out by the authors about the behavior of 80 MPa characteristic compression strength concrete reinforced with different amount of high carbon content steel fiber, submit to impact of different caliber projectiles, determining the thickness of this type of concrete walls needs to prevent no perforation, as well as the maximum penetration to reach into them, so that in the event of no perforation and only penetration, "scabbing" phenomena does not take place on the rear surface of the wall. Prior to ballistic testing was necessary to design the high-strength concrete with specific mechanical properties, especially those related to ductility, since these special concrete must absorb the high energy of projectiles and also the shock waves that accompany them.Este trabajo presenta los resultados de la investigación llevada a cabo por los autores sobre el comportamiento de hormigón de 80 MPa de resistencia característica a compresión reforzado con diferentes cuantías de fibras de acero de alto contenido en carbono sometido al impacto de proyectiles de distintos calibres, determinando el espesor de muros de este tipo de hormigón que sería preciso disponer para impedir su perforación por dichos proyectiles, así como los valores máximos de penetración, para que en el caso de no producirse perforación y sólo penetración, no se genera cráter, “scabbing”, en el trasdós de los mismos. Previamente a los ensayos balísticos fue preciso diseñar los hormigones para que, presentaran determinadas características mecánicas, especialmente las relacionadas con la ductilidad, dado que estos hormigones especiales deben absorber la elevada energía que le transmiten los proyectiles y las ondas de choque que los acompañan.

  4. Observation of wounding characteristics in dogs wounded by super velocity projectile

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To understand wounding characteristics in dogs woundedby super velocity projectile with a purpose of providing a basis for prevention and treatment of such wounds.Methods: A specially-made explosive gun was used to shoot aluminium bullet weighing 3.0 g and 1.4 g to injure both legs of dogs at velocities of 2 330 m/s, 3 200 m/s and 4 250 m/s, respectively, and the soap specially made was also shot. At the same time, steel ball of 1.03 g was shot with a Type 53 smooth chamber gun at a speed of 1 280 m/s. Within 30 min after wounding, debridement and pathological anatomy were performed and specimens were taken for light microscope observation.Results: When the dogs were wounded by the 3 g bullet at speed of 2 330 m/s, the entrance of the left leg was penetrated explosively with a defect area of 225 cm2, and the femur trunk was also injured and the residual femur had comminution fracture. The exit of the right leg was blindly wounded with a defect area of 63 cm2, but only the skin was not penetrated. Both testes and part pelvis were injured too. Under light microscope, degenerative myofibers and bleeding of the spatium between the myofibers could be found at the place 4 cm away from the wounding track. Furthermore, serious bleeding of the bladder and blood vessels of the brain could be observed. The lungs showed changes of blast injury. Vacuolar change was presented in the cytoplasm of hepatocytes. Injuries of the animals in other two experimental groups were similar to those described above, but the defect area of the wounded track was 124 cm2 in the group of 4 250 m/s. Injuries caused by the steel ball were milder than caused by the explosive gun. The volume of the residual cavity in the soap was 5 000 ml.Conclusions: The super-velocity projectile causes destructive damage to the local tissues and multi-organ injuries. Therefore, the practical medical care needs not only amputation but also management of multi-organ injuries.

  5. Characteristics study of projectiles lightest fragment for 84Kr36 - emulsion interaction at around 1 A GeV

    CERN Document Server

    Marimuthu, N; Inbanathan, S S R

    2016-01-01

    The present article significantly investigated projectiles lightest fragments (proton) multiplicity distribution and probability distribution with 84Kr36 emulsion collision at around 1 A GeV. The multiplicity and normalized multiplicity of projectiles lightest fragments (proton) is correlated with the compound particles, shower particles, black particles, grey particles, helium fragments particles and heavily ionizing charged particles. It is found that projectiles lightest fragments (proton) are strongly correlated with compound particles and shower particles rather than other particles and the average multiplicity of projectiles lightest fragments (proton) increases with increasing compound, shower and heavy ionizing particles. Normalized projectiles lightest fragments (proton) are strongly correlated with compound particles, shower particles and heavy ionizing charge particles. The multiplicity distribution of the projectiles lightest fragments (proton) emitted in the 84Kr36 + emulsion interaction at aroun...

  6. Production and transport of the excited states of projectile ions in ion-solid interaction; Production et transport des etats excites du projectile en interaction ion-solide

    Energy Technology Data Exchange (ETDEWEB)

    Lamour, E

    1997-11-01

    In ion-solid collisions, more excited states of projectile ions with high angular momenta l are populated than in ion-atom collisions. The use of 13.6 MeV/u Ar{sup 18+} projectile ions and solid carbon targets allowed us to study Ar{sup 17+} excited states initially populated by electron capture. Using various targets with increasing thickness from 3.5 to 200 {mu}g/cm{sup 2}, the evolution of excited states from the single collision condition to the population equilibrium was investigated. We observed the evolution of the Lyman line intensities as a function of the ion transit time inside the target (sensitive to core state population) and as a function of the ion time of flight behind the target (sensitive to Rydberg state population). To explain the experimental results, a complete theoretical analysis of the transport of excited states inside the medium was performed. We used two different collisional models. The first one is a rate equation model based on a statistical description of binary collisions of the projectile with target atoms. The second one is a classical transport theory based on an equation describing the motion of the projectile electron on a classical orbit perturbed by a stochastic force. A comparison with experiment shows that such a collisional approach allows to interpret the excited l-state population, but fails in describing the core state population. The observed l mixing in these states is much larger than predicted by the models. The polarization of the medium induced by the projectile ion, with both models do not take into account, could be responsible for this mixing by means of the Stark effect. (author)

  7. Hypervelocity impact of rod projectiles with L/D from 1 to 32

    International Nuclear Information System (INIS)

    Beside a short remark on the ''hydrodynamic theory of rod projectiles'', the paper deals with the terminal ballistic behaviour of cylindrical projectiles against semi-infinite targets. Experimental data of EMI, completed by results of some other authors, are presented. Crater parameters like depth, diameter and volume and their dependence on projectile velocity (up to 5000 m/s), projectile and target material properties, as well as L/D-ratios (1 - 32), are discussed. Mainly the projectile materials steel and tungsten sinter-alloys are considered. Target materials are mild steel and high strength steel, an Al-alloy and a tungsten sinter-alloy. The results show that the influence of material density on the crater dimensions is considerably greater than the influence of strength. The L/D ratio determines the velocity dependence of crater depth, diameter and volume. At high velocities in the hydrodynamic regime, the crater depth of short cylinders (L/D -- 1) is approximately proportional to v/sub p//sup 2/3/ (v/sub p/ = projectile velocity). With increasing L/D-ratio, the slope of the penetration curves decreases and converges for rods (L/D >> 1) versus a saturation, i.e. becomes nearly independent on v/sub p/. A consequence of this saturation is the existence of a so-called ''tangent velocity'', above which an optimal increase of efficiency is only realized by increasing the projectile mass and not the velocity. Furthermore, ballistic limits of real targets like single plates and symmetric double plates meteorite bumper shield) are taken into account. The expected better performance of ''segmented rods'' is also discussed

  8. Target-projectile interaction during impact melting at Kamil Crater, Egypt

    Science.gov (United States)

    Fazio, Agnese; D'Orazio, Massimo; Cordier, Carole; Folco, Luigi

    2016-05-01

    In small meteorite impacts, the projectile may survive through fragmentation; in addition, it may melt, and chemically and physically interact with both shocked and melted target rocks. However, the mixing/mingling between projectile and target melts is a process still not completely understood. Kamil Crater (45 m in diameter; Egypt), generated by the hypervelocity impact of the Gebel Kamil Ni-rich ataxite on sandstone target, allows to study the target-projectile interaction in a simple and fresh geological setting. We conducted a petrographic and geochemical study of macroscopic impact melt lapilli and bombs ejected from the crater, which were collected during our geophysical campaign in February 2010. Two types of glasses constitute the impact melt lapilli and bombs: a white glass and a dark glass. The white glass is mostly made of SiO2 and it is devoid of inclusions. Its negligible Ni and Co contents suggest derivation from the target rocks without interaction with the projectile (compression stage and the excavation stage, projectile and target liquids formed at their interface and chemically interact in a restricted zone. Projectile contamination affected only a shallow portion of the target rocks. The SiO2 melt that eventually solidified as white glass behaved as an immiscible liquid and did not interact with the projectile. During the excavation stage dark glass melt engulfed and coated the white glass melt, target fragments, and got stuck to iron meteorite shrapnel fragments. This model could also explain the common formation of white and dark glasses in small impact craters generated by iron bodies (e.g., Wabar).

  9. Progress in spheromaks for power amplification and transfer to hypervelocity projectiles

    International Nuclear Information System (INIS)

    The goal of the spheromak program at Los Alamos is to develop a new scheme to accelerate material objects to hypervelocities (velocities above a few kilometers per second). This capability would provide a valuable tool to other research programs, such as weapons lethality tests, studies of the properties of materials at extremely high pressures, and magnetically-insulated impact fusion. In the authors' scheme, the magnetized spheromak plasma, confined by a metallic wall, would act as an energy storage and transfer medium. As high explosives (HE) compress part of the metallic wall against the spheromak magnetic field, the spheromak stores energy. Once the spheromak reaches a critical dimension, the MHD equilibrium is expected to switch (much faster than the compression time) to a new configuration, which is the minimum-energy state of the new geometry. This witching action would result in the spheromak magnetic field imparting a sudden, strong pressure to a small section of the wall, which would then break away as an accelerated projectile. The scheme, including the basis for the spheromak switching effect, are described

  10. The African Origin of Complex Projectile Technology: An Analysis Using Tip Cross-Sectional Area and Perimeter

    OpenAIRE

    Shea, John J.; Matthew L. Sisk

    2011-01-01

    Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cros...

  11. Chemical projectile-target interaction during hypervelocity cratering experiments (MEMIN project).

    Science.gov (United States)

    Ebert, M.; Hecht, L.; Deutsch, A.; Kenkmann, T.

    2012-04-01

    The detection and identification of meteoritic components in impact-derived rocks are of great value for confirming an impact origin and reconstructing the type of extraterrestrial material that repeatedly stroke the Earth during geologic evolution [1]. However, little is known about processes that control the projectile distribution into the various impactites that originate during the cratering and excavation process, and inter-element fractionation between siderophile elements during impact cratering. In the context of the MEMIN project, cratering experiments have been performed using spheres of Cr-V-Co-Mo-W-rich steel and of the iron meteorite Campo del Cielo (IAB) as projectiles accelerated to about 5 km/s, and blocks of Seeberger sandstone as target. The experiments were carried out at the two-stage acceleration facilities of the Fraunhofer Ernst-Mach-Institute (Freiburg). Our results are based on geochemical analyses of highly shocked ejecta material. The ejecta show various shock features including multiple sets of planar deformations features (PDF) in quartz, diaplectic quartz, and partial melting of the sandstone. Melting is concentrated in the phyllosilicate-bearing sandstone matrix but involves quartz, too. Droplets of molten projectile have entered the low-viscosity sandstone melt but not quartz glass. Silica-rich sandstone melts are enriched in the elements that are used to trace the projectile, like Fe, Ni, Cr, Co, and V (but no or little W and Mo). Inter-element ratios of these "projectile" tracer elements within the contaminated sandstone melt may be strongly modified from the original ratios in the projectiles. This fractionation most likely result from variation in the lithophile or siderophile character and/or from differences in reactivity of these tracer elements with oxygen [2] during interaction of metal melt with silicate melt. The shocked quartz with PDF is also enriched in Fe and Ni (experiment with a meteorite iron projectile) and in Fe

  12. Hydrocode Simulation with Modified Johnson-Cook Model and Experimental Analysis of Explosively Formed Projectiles

    Science.gov (United States)

    Hussain, G.; Hameed, A.; Hetherington, J. G.; Barton, P. C.; Malik, A. Q.

    2013-04-01

    The formation of mild steel (MS) and copper (Cu) explosively formed projectiles (EFPs) was simulated in AUTODYN using both the Johnson-Cook (JC) and modified Johnson-Cook (JCM) constitutive models. The JC model was modified by increasing the hardening constant by 10%. The previously established semi-empirical equations for diameter, length, velocity, and depth of penetration were used to verify the design of the EFP. The length-to-diameter (L/D) ratio of the warhead used in the simulation varied between 1 < L/D < 2. To avoid projectile distortion or breakup for large standoff applications, the design of the EFP warhead was modified to obtain a lower L/D ratio. Simulations from the JC model underestimated the EFP diameter, resulting in an unrealistically elongated projectile. This shortcoming was resolved by employing the JCM model, giving good agreement with the experimental results. The projectile velocity and hole characteristics in 10-mm-thick aluminum target plates were studied for both models. The semi-empirical equations and the JC model overestimated the projectile velocity, whereas the JCM model underestimated the velocity slightly when compared to the experimental results. The depths of penetration calculated by the semi-empirical equations in the aluminum (Al) target plate were 55 and 52 mm for Cu and MS EFPs, respectively.

  13. Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

    Directory of Open Access Journals (Sweden)

    Aizik F.

    2012-08-01

    Full Text Available In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile’s core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

  14. Accuracy Improvement Capability of Advanced Projectile Based on Course Correction Fuze Concept

    Directory of Open Access Journals (Sweden)

    Ahmed Elsaadany

    2014-01-01

    Full Text Available Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course correction modules, one is devoted to range correction (drag ring brake and the second is devoted to drift correction (canard based-correction fuze. The course correction modules have been characterized by aerodynamic computations and flight dynamic investigations in order to analyze the effects on deflection of the projectile aerodynamic parameters. The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved. The drag ring brake is found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in large range correction. The correction occasion time can be predefined depending on required correction of range. On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate. In addition, the canard extension induces a high-frequency incidence angle as canards reciprocate at the roll motion.

  15. CO2 Cluster Ion Beam, an Alternative Projectile for Secondary Ion Mass Spectrometry

    Science.gov (United States)

    Tian, Hua; Maciążek, Dawid; Postawa, Zbigniew; Garrison, Barbara J.; Winograd, Nicholas

    2016-06-01

    The emergence of argon-based gas cluster ion beams for SIMS experiments opens new possibilities for molecular depth profiling and 3D chemical imaging. These beams generally leave less surface chemical damage and yield mass spectra with reduced fragmentation compared with smaller cluster projectiles. For nanoscale bioimaging applications, however, limited sensitivity due to low ionization probability and technical challenges of beam focusing remain problematic. The use of gas cluster ion beams based upon systems other than argon offer an opportunity to resolve these difficulties. Here we report on the prospects of employing CO2 as a simple alternative to argon. Ionization efficiency, chemical damage, sputter rate, and beam focus are investigated on model compounds using a series of CO2 and Ar cluster projectiles (cluster size 1000-5000) with the same mass. The results show that the two projectiles are very similar in each of these aspects. Computer simulations comparing the impact of Ar2000 and (CO2)2000 on an organic target also confirm that the CO2 molecules in the cluster projectile remain intact, acting as a single particle of m/z 44. The imaging resolution employing CO2 cluster projectiles is improved by more than a factor of two. The advantage of CO2 versus Ar is also related to the increased stability which, in addition, facilitates the operation of the gas cluster ion beams (GCIB) system at lower backing pressure.

  16. On the universal scaling in the electronic stopping cross section for heavy ion projectiles

    Science.gov (United States)

    Cabrera-Trujillo, R.; Martínez-Flores, C.; Trujillo-López, L. N.; Serkovic-Loli, L. N.

    2016-02-01

    Energy deposition of heavy ions when penetrating a material is of crucial importance in determining the damage to materials with implications in areas such as material science, plasma physics, radiotherapy and dosimetry. Due to the N-body electron problem, it has been thought that the electronic stopping cross section is unique for a given projectile-target combination and differs from system to system. In this work, we show that within the Bethe theory, there is a universal scaling when the electronic stopping cross sections and projectile kinetic energy are scaled properly in terms of the target mean excitation energy, ?, for all projectile-target combinations. We show that the scaling is given by ? as a function of ?, thus showing the importance of the characterization of the mean excitation energy. The scaling law expresses a systematic and universal behavior among complex projectile-target systems in the energy deposition, characterized by the minimum momentum transfer during the slowing down process. We provide an analytic expression for the universal scaling law for the stopping cross section of any projectile-target combination valid at high collision energies. Finally, we verify the universal scaling law by comparison to atomic and molecular experimental data available in the literature. We expect our findings will motivate further experimental work to verify our universal scaling for more complex systems in the absence of experimental data.

  17. EXPERIMENTAL AND THEORETICAL STUDY ON THE HIGH-SPEED HORIZONTAL WATER ENTRY BEHAVIORS OF CYLINDRICAL PROJECTILES

    Institute of Scientific and Technical Information of China (English)

    GUO Zi-tao; ZHANG Wei; WANG Cong

    2012-01-01

    In this article,the horizontal water-entry of flat-nose projectiles of two different lengths at impact velocities of 400 r/s-600 m/s is studied experimentally and theoretically.Based on the solution of the Rayleigh-Besant problem,a set of projectile dynamic equations are derived and a cavity model is built to describe the projectile's water entry dynamics.A parameter in the cavity model is determined by employing the principle of energy conservation.The results indicate that the flat-nose projectiles enjoy a good stability of trajectory,the drag coefficient and the velocity decay coefficient are dependent on the cavitation number,and increase along the penetration distance but with a relatively small variation.The maximum cavity radius decreases monotonically with the penetration distance.Projectiles with the same nose shapes at different initial velocities have a basically consistent cavity dimension before the deep pinching off phenomenon occurs.Good agreements are observed between results obtained by the analytical model and the experimental results.

  18. A Technique for Obtaining Hypervelocity Impact Data by using the Relative Velocities of Two Projectiles

    Science.gov (United States)

    Kinard, William H.; Collins, Rufus D., Jr.

    1961-01-01

    A facility has been developed and put into operation to determine the feasibility of obtaining hypervelocity impact data by using the relative velocities of two projectiles. The facility utilizes the technique of firing a target toward an oncoming high-velocity projectile so that the impact velocity is equal to the sum of the projectile velocity and the target velocity. A 37-millimeter powder gun is utilized to accelerate the targets, and a specially designed 22-caliber light-gas gun accelerates the impacting projectiles. The light-gas gun is operated by detonating an explosive charge which permits it to be synchronized with the firing of the 37-millimeter gun. Impact velocities as great as 21,850 ft/sec have been obtained during development of the facility. After the oncoming projectiles impact the targets fired from the 37-millimeter gun, these targets are recovered by allowing them to impact into Celotex and soft wooden blocks. The craters formed in the targets then can be observed and measured. The results of several preliminary firings of the facility are included in this report.

  19. Numerical Investigation of Bending-Body Projectile Aerodynamics for Maneuver Control

    Science.gov (United States)

    Youn, Eric; Silton, Sidra

    2015-11-01

    Precision munitions are an active area of research for the U.S. Army. Canard-control actuators have historically been the primary mechanism used to maneuver fin-stabilized, gun-launched munitions. Canards are small, fin-like control surfaces mounted at the forward section of the munition to provide the pitching moment necessary to rotate the body in the freestream flow. The additional lift force due to the rotated body and the canards then alters the flight path toward the intended target. As velocity and maneuverability requirements continue to increase, investigation of other maneuver mechanisms becomes necessary. One option for a projectile with a large length-to-diameter ratio (L/D) is a bending-body design, which imparts a curvature to the projectile body along its axis. This investigation uses full Navier-Stokes computational fluid dynamics simulations to evaluate the effectiveness of an 8-degree bent nose tip on an 8-degree bent forward section of an L/D =10 projectile. The aerodynamic control effectiveness of the bending-body concept is compared to that of a standard L/D =10 straight-body projectile as well as that of the same projectile with traditional canards. All simulations were performed at supersonic velocities between Mach 2-4.

  20. Normal and Oblique Impacts of Hard Projectile on Single and Layered Plates-An Experimental Study

    Directory of Open Access Journals (Sweden)

    V. Madhu

    2003-04-01

    Full Text Available The phenomenon of ordnance velocity impact of projectile on single and layered plates is of interest for many applications. In this paper. an experimental study of normal and oblique impacts or an ogive shaped, hard steel projectile on single and layered plates of mild steel and aluminium is presented. The projectiles were fired at an impact velocity of about 820 ms-1. The plate thickness was varied in the range 10 mm to 40 mm and the ratio of plate thickness to the diameter of the projectile varied in the range 1.5 to 13.0. Observations on target damage and measurements of incident and residual velocities for different angles of impact are presented. Plate thickness t*, for which the incident velocity is the ballistic limit, is determined. Computer simulations were carried out using a hydrodynamic code to simulate the normal impact of a projectile and compared these with the experimental results. Experiments were performed to evaluate the response of these plates of intermediate thickness when layered. and the results were compared to the results of single plate of same total thickness.

  1. Light-ion elastic scattering potentials: Energy and projectile-mass dependence

    International Nuclear Information System (INIS)

    Volume integrals of the real potentials derived from elastic scattering studies of deuterons, tritons, 3He, and α particles have been calculated for data available from the lowest to the highest energy. These volume integrals have been plotted as a function of energy per nucleon for each projectile. By selecting energy regions where there were least ambiguities in the potentials and averaging the volume integrals in 1 MeV bins, the energy dependences were determined. The volume integrals show a logarithmic dependence on the energy per nucleon. The zero crossing of the potentials is at about the same value of ∼650 MeV/nucleon for all projectiles. With increasing projectile mass, the potentials become weaker, possibly due to Pauli blocking effects in the projectile. Neutron-rich projectiles have smaller volume integrals due to the manifestation of the isospin effect. A similar analysis of the imaginary volume integrals shows that they increase from zero at the lowest energies to about 100-150 MeV fm3 around 10 MeV/nucleon and then remain essentially constant

  2. CO2 Cluster Ion Beam, an Alternative Projectile for Secondary Ion Mass Spectrometry

    Science.gov (United States)

    Tian, Hua; Maciążek, Dawid; Postawa, Zbigniew; Garrison, Barbara J.; Winograd, Nicholas

    2016-09-01

    The emergence of argon-based gas cluster ion beams for SIMS experiments opens new possibilities for molecular depth profiling and 3D chemical imaging. These beams generally leave less surface chemical damage and yield mass spectra with reduced fragmentation compared with smaller cluster projectiles. For nanoscale bioimaging applications, however, limited sensitivity due to low ionization probability and technical challenges of beam focusing remain problematic. The use of gas cluster ion beams based upon systems other than argon offer an opportunity to resolve these difficulties. Here we report on the prospects of employing CO2 as a simple alternative to argon. Ionization efficiency, chemical damage, sputter rate, and beam focus are investigated on model compounds using a series of CO2 and Ar cluster projectiles (cluster size 1000-5000) with the same mass. The results show that the two projectiles are very similar in each of these aspects. Computer simulations comparing the impact of Ar2000 and (CO2)2000 on an organic target also confirm that the CO2 molecules in the cluster projectile remain intact, acting as a single particle of m/z 44. The imaging resolution employing CO2 cluster projectiles is improved by more than a factor of two. The advantage of CO2 versus Ar is also related to the increased stability which, in addition, facilitates the operation of the gas cluster ion beams (GCIB) system at lower backing pressure.

  3. Screening and antiscreening by projectile electrons in high-velocity atomic collisions

    International Nuclear Information System (INIS)

    The scattering amplitude for a projectile of nuclear charge Z1 carrying N electrons colliding with an atomic target with charge Z2, evaluated in the first Born approximation using hydrogenic wave functions, is compared with recent experimental results. In the present approximation where the minimum momentum transfer t/sub min/ is considered to be approximately independent of the final state of the projectile, the differential cross sections separate into a product of one term that depends only on the target times the square Z21(t) of an effective projectile charge. Here an analytic expression for Z21(t) is given for 2, 1, and 0 electrons. Some total ionization cross-section ratios are also given

  4. A study of the perforation of stiffened plates by rigid projectiles

    Institute of Scientific and Technical Information of China (English)

    Jianguo Ning; Weidong Song; Jing Wang

    2005-01-01

    In the present paper, a four-stage perforation model that accurately predicts the residual velocity is developed by adopting an energy method. The four stages are plug formation, dishing formation, petal formation and projectile exit. In addition, some important experimental results are presented and analyzed to validate the present perforation model. In the experiments, high speed camera system is used to record the perforation process. Observations on target damage and measurements of initial velocities and residual velocities with the aid of the system are presented. Numerical simulations are carried out for projectiles against single and layered plates adopted in the experiments. The perforation process is studied and the deformation and failure modes are obtained. The predictions of numerical simulations and analytical model are found in reasonably good agreement with those of experiments, and can be used to predict the ballistic limit and residual velocity of stiffened plates perforated by rigid projectiles.

  5. Probable Projectile-Target Combinations for the Synthesis of Super Heavy Nucleus 286112

    Directory of Open Access Journals (Sweden)

    K. P. Santhosh

    2014-02-01

    Full Text Available The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of 286112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus 286112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems 82Ge + 204Hg, 80Ge + 206Hg and 78Zn + 208Pb found in the deep cold valley region and the systems 48Ca+238U, 38S+248Cm and 44Ar+242Pu in the cold valleys are predicted to be the better optimal projectile-target combinations for the synthesis of super heavy nucleus 286112.

  6. Meso-scale hypervelocity cratering experiments (MEMIN project): Characterization of projectile material

    Science.gov (United States)

    Domke, Isabelle; Deutsch, Alex; Hecht, Lutz; Kenkmann, Thomas; Berndt, Jasper

    2010-05-01

    The DFG-funded "MEMIN" (multidisciplinary experimental and modelling impact crater research network) research group is aimed at a better understanding of the impact cratering process by combining (i) numerical modelling of crater formation, (ii) investigation of terrestrial craters and (iii) meso-scale hypervelocity impact experiments using the large two-stage light gas gun at the Ernst-Mach-Institute (EMI; Efringen-Kirchen, Germany). In the framework of MEMIN, 1 cm-sized projectiles of the steel SAE 4130 (mass of 4.1 g) have been fired with a velocity of ~ 5.3 km s-1 onto blocks of Seeberger sandstone (size 100 x 100 x 50 cm, grain size 169+/-8 μm; porosity 12-20 vol.%). One goal of MEMIN is to document, analyze, and understand the fate of the projectile and its distribution between crater and ejecta; hence, the use of well-analyzed projectile material is mandatory. For this purpose, we use optical, and electron microscopy, electron microprobe (WWU, and MfN), and LA-ICP-MS microanalysis (WWU). Currently we evaluate which steel or iron meteorite is adequate for the intended use. Important properties of a projectile are (i) textural and chemical homogeneity, (ii) clear chemical distinction to the target sandstone, (iii) presence of elements such as Co, Ni, Cr, PGE that as "meteoritic component" are used in terrestrial craters to trace projectile matter, and characterize the type of the projectile (i.e., meteorite group), and finally (iv) mechanical properties that guarantee stability during sphere production, launch and flight. Strong chemical differences to the target material and geochemical homogeneity of the projectile will allow detection of small volumes of projectile matter by high spatial resolution in-situ analysis with the LA-ICP-MS. Steel SAE 4130 is heterogeneous at the 100-µm scale and has low trace element contents. In future, we plan the use of the alloyed heat treatable steel D290-1 as projectile as its texture is quite homogenous at the scale of

  7. Probable projectile-target combinations for the synthesis of super heavy nucleus $^{286}$112

    CERN Document Server

    Santhosh, K P

    2014-01-01

    The fusion cross sections for the reactions of all the projectile-target combinations found in the cold valleys of $^{286}$112 have been studied using scattering potential as the sum of Coulomb and proximity potential, so as to predict the most probable projectile-target combinations in heavy ion fusion reactions for the synthesis of super heavy nucleus $^{286}$112. While considering the nature of potential pockets and half lives of the colliding nuclei, the systems $^{82}$Ge + $^{204}$Hg, $^{80}$Ge + $^{206}$Hg and $^{78}$Zn + $^{208}$Pb found in the deep cold valley region and the systems $^{48}$Ca+$^{238}$U, $^{38}$S+$^{248}$Cm and $^{44}$Ar+$^{242}$Pu in the cold valleys are predicted to be the better optimal projectile-target combinations for the synthesis of super heavy nucleus $^{286}$112.

  8. Ground target localization algorithm for semi-active laser terminal correction projectile

    Directory of Open Access Journals (Sweden)

    Xing-long Li

    2016-06-01

    Full Text Available A target localization algorithm, which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position, is proposed to obtain the accurate position of ground target in real time in the trajectory correction process of semi-active laser terminal correction projectile. A target localization model is established according to projectile position, attitude and line-of-sight angle. The effects of measurement errors of projectile position, attitude and line-of-sight angle on localization accuracy at different quadrant elevation angles are analyzed through Monte-Carlo simulation. The simulation results show that the measurement error of line-of-sight angle has the largest influence on the localization accuracy. The localization accuracy decreases with the increase in quadrant elevation angle. However, the maximum localization accuracy is less than 7 m. The proposed algorithm meets the accuracy and real-time requirements of target localization.

  9. Extended Range of a Gun Launched Smart Projectile Using Controllable Canards

    Directory of Open Access Journals (Sweden)

    Mark Costello

    2001-01-01

    Full Text Available This effort investigates the extent to which moveable canards can extend the range of indirect fire munitions using both projectile body and canard lift. Implications on terminal velocity and time of flight using this mechanism to extend range are examined for various canard configurations. Performance predictions are conducted using a six-degree-of-freedom simulation model that has previously been validated against range data. The projectile dynamic equations are formed in the body frame and aerodynamic loads from the body and canards are Mach number and angle of attack dependent. The projectile body aerodynamic moments include unsteady aerodynamic damping. The focus of the study is directed toward low cost competent munitions that extend range and as such a simple flight control system is considered which utilizes only timer, roll rate, and roll attitude inputs.

  10. Projectile motion of a once rotating object: physical quantities at the point of return

    Science.gov (United States)

    Arabasi, Sameer

    2016-09-01

    Vertical circular motion is a widely used example to explain non-uniform circular motion in most undergraduate general physics textbooks. However, most of these textbooks do not elaborate on the case when this motion turns into projectile motion under certain conditions. In this paper, we describe thoroughly when a mass attached to a cord, moving in a vertical circular motion, turns into a projectile and its location and velocity when it rejoins the circular orbit. This paper provides an intuitive understanding, supported by basic kinematic equations, to give an interesting elegant connection between circular motion and projectile motion—something lacking in most physics textbooks—and will be very useful to present to an undergraduate class to deepen their understanding of both models of motion.

  11. Systematic study of probable projectile-target combinations for the synthesis of the superheavy nucleus 302120

    Science.gov (United States)

    Santhosh, K. P.; Safoora, V.

    2016-08-01

    Probable projectile-target combinations for the synthesis of the superheavy element 302120 have been studied taking the Coulomb and proximity potential as the interaction barrier. The probabilities of the compound nucleus formation PCN for the projectile-target combinations found in the cold reaction valley of 302120 are estimated. At energies near and above the Coulomb barrier, we have calculated the capture, fusion, and evaporation residue cross sections for the reactions of all probable projectile-target combinations so as to predict the most promising projectile-target combinations for the synthesis of the superheavy element 302120 in heavy-ion fusion reactions. The calculated fusion and evaporation cross sections for the more asymmetric ("hotter") projectile-target combination is found to be higher than the less asymmetric ("colder") combination. It can be seen from the nature of the quasifission barrier height, mass asymmetry, the probability of compound nucleus formation, survival probability, and excitation energy, the systems 44Ar+258No , 46Ar+256No , 48Ca+254Fm , 50Ca+252Fm , 54Ti+248Cf , and 58Cr+244Cm in deep region I of the cold reaction valley and the systems 62Fe+240Pu , 64Fe+238Pu , 68Ni+234U , 70Ni+232U , 72Ni+230U , and 74Zn+228Th in the other cold valleys are identified as the better projectile-target combinations for the synthesis of 302120. Our predictions on the synthesis of 302120 superheavy nuclei using the combinations 54Cr+248Cm , 58Fe+244Pu , 64Ni+238U , and 50Ti+249Cf are compared with available experimental data and other theoretical predictions.

  12. Penetration experiments in aluminum 1100 targets using soda-lime glass projectiles

    Science.gov (United States)

    Horz, Friedrich; Cintala, Mark J.; Bernhard, Ronald P.; Cardenas, Frank; Davidson, William E.; Haynes, Gerald; See, Thomas H.; Winkler, Jerry L.

    1995-01-01

    The cratering and penetration behavior of annealed aluminum 1100 targets, with thickness varied from several centimeters to ultra-thin foils less than 1 micrometer thick, were experimentally investigated using 3.2 mm diameter spherical soda-lime glass projectiles at velocities from 1 to 7 km/s. The objective was to establish quantitative, dimensional relationships between initial impact conditions (impact velocity, projectile diameter, and target thickness) and the diameter of the resulting crater or penetration hole. Such dimensional relationships and calibration experiments are needed to extract the diameters and fluxes of hypervelocity particles from space-exposed surfaces and to predict the performance of certain collisional shields. The cratering behavior of aluminum 1100 is fairly well predicted. However, crater depth is modestly deeper for our silicate impactors than the canonical value based on aluminum projectiles and aluminum 6061-T6 targets. The ballistic-limit thickness was also different. These differences attest to the great sensitivity of detailed crater geometry and penetration behavior on the physical properties of both the target and impactor. Each penetration experiment was equipped with a witness plate to monitor the nature of the debris plume emanating from the rear of the target. This plume consists of both projectile fragments and target debris. Both penetration hole and witness-plate spray patterns systematically evolve in response to projectile diameter/target thickness. The relative dimensions of the projectile and target totally dominate the experimental products documented in this report; impact velocity is an important contributor as well to the evolution of penetration holes, but is of subordinate significance for the witness-plate spray patterns.

  13. Distorted wave theories for dressed-ion-atom collisions with GSZ projectile potentials

    Energy Technology Data Exchange (ETDEWEB)

    Monti, J M; Rivarola, R D [Instituto de Fisica Rosario (CONICET-UNR) and Facultad de Ciencias Exactas, IngenierIa y Agrimensura, Universidad Nacional de Rosario, Avenida Pellegrini 250, 2000 Rosario (Argentina); Fainstein, P D, E-mail: monti@ifir-conicet.gov.ar [Comision Nacional de EnergIa Atomica, Centro Atomico Bariloche, 8400 San Carlos de Bariloche (Argentina)

    2011-10-14

    The continuum distorted wave and the continuum distorted wave-eikonal initial state approximations for electron emission in ion-atom collisions are generalized to the case of dressed projectiles. The interaction between the dressed projectile and the active electron is represented by the analytic Green-Sellin-Zachor (GSZ) potential. Doubly differential cross sections as a function of the emitted electron energy and angle are computed. The region of the binary encounter peak is analysed in detail. Interference structures appear in agreement with the experimental data and are interpreted as arising from the coherent interference between short- and long-range scattering amplitudes.

  14. Development of odd-Z-projectile reactions for transactinide element synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Folden, III, Charles Marvin [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The development of new odd-Z-projectile reactions leading to the production of transactinide elements is described. The cross section of the even-Z-projectile 208Pb(64Ni, n)271Ds reaction was measured at two new energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, seven decay chains attributable to 271Ds were observed. These data, combined with previous results, establish an excitation function for the production of 271Ds. The maximum cross section was 20 +15 -11 pb at a center-of-target energy of 311.5 MeV in the laboratory frame.The data from the 271Ds experiments were used to estimate the optimum beam energy for the new odd-Z-projectile 208Pb(65Cu, n)272-111 reaction using the Fusion by Diffusion theory proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. A cross section for this reaction was measured for the first time, at a center-of-target energy of 321.1 MeV in the laboratory frame. The excitation energy f or compound nuclei formed at the target center was 13.2 MeV. One decay chain was observed, resulting in a measured cross section of 1.7 +3.9 -1.4 pb. This decay chain is in good agreement with previously published data on the decay of 272-111.The new odd-Z-projectile 208Pb(55Mn, n)262Bh reaction was studied at three different projectile energies, and 33 decay chains of 262Bh were observed. The existence of a previously reported alpha-decaying isomeric state in this nuclide was confirmed. Production of the ground state was preferred at all three beam energies. The maximum cross section was 540 +180 -150 pb at a projectile center-of-target energy of 264.0 MeV. This cross section is much larger than that previously reported for the even-Z-projectile 209Bi(54Cr, n)262Bh reaction, which may be because the 54Cr projectile

  15. The african origin of complex projectile technology: an analysis using tip cross-sectional area and perimeter.

    Science.gov (United States)

    Sisk, Matthew L; Shea, John J

    2011-01-01

    Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cross-Sectional Perimeter, a more accurate proxy of the force needed to penetrate a target to a lethal depth. The current study discusses this measure and uses it to analyze a collection of measurements from African Middle Stone Age pointed stone artifacts. Several point types that were rejected in previous studies are statistically indistinguishable from ethnographic projectile points using this new measure. The ramifications of this finding for a Middle Stone Age origin of complex projectile technology is discussed.

  16. The African Origin of Complex Projectile Technology: An Analysis Using Tip Cross-Sectional Area and Perimeter

    Directory of Open Access Journals (Sweden)

    Matthew L. Sisk

    2011-01-01

    Full Text Available Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cross-Sectional Perimeter, a more accurate proxy of the force needed to penetrate a target to a lethal depth. The current study discusses this measure and uses it to analyze a collection of measurements from African Middle Stone Age pointed stone artifacts. Several point types that were rejected in previous studies are statistically indistinguishable from ethnographic projectile points using this new measure. The ramifications of this finding for a Middle Stone Age origin of complex projectile technology is discussed.

  17. Systematic study on probable projectile-target combinations for the synthesis of the $^{302}$120 superheavy nucleus

    CERN Document Server

    Santhosh, K P

    2016-01-01

    Probable projectile-target combinations for the synthesis of superheavy element $^{302}$120 have been studied taking Coulomb and proximity potential as the interaction barrier. The probabilities of compound nucleus formation, PCN for the projectile-target combinations found in the cold reaction valley of $^{302}$120 are estimated. At energies near and above the Coulomb barrier, we have calculated the capture, fusion and evaporation residue cross sections for the reactions of all the probable projectile-target combinations so as to predict the most promising projectile-target combinations for the synthesis of SHE $^{302}$120 in heavy ion fusion reactions. The calculated fusion and evaporation cross section for the more asymmetric (hotter) projectile-target combination is found to be higher than the less asymmetric (colder) combination. It can be seen from the nature of quasi-fission barrier height, mass asymmetry, probability of compound nucleus formation, survival probability and excitation energy, the system...

  18. On projectile fragmentation at high-velocity perforation of a thin bumper

    Science.gov (United States)

    Myagkov, N. N.; Stepanov, V. V.

    2014-09-01

    By means of 3D numerical simulations, we study the statistical properties of the fragments cloud formed during high-velocity impact of a spherical projectile on a mesh bumper. We present a quantitative description of the projectile fragmentation, and study the nature of the transition from the damage to the fragmentation of the projectile when the impact velocity varies. A distinctive feature of the present work is that the calculations are carried out by smoothed particle hydrodynamics (SPH) method applied to the equations of mechanics of deformable solids (MDS). We describe the materials behavior by the Mie-Grüneisen equation of state and the Johnson-Cook model for the yield strength. The maximum principal stress spall model is used as the fracture model. It is shown that the simulation results of fragmentation based on the MDS equations by the SPH method are qualitatively consistent with the results obtained earlier on the basis of the molecular dynamics and discrete element models. It is found that the power-law distribution exponent does not depend on energy imparted to the projectile during the high-velocity impact. At the same time, our calculations show that the critical impact velocity, the power-law exponent and other critical exponents depend on the fracture criterion.

  19. Estimating the excitation energy of the primary projectile like fragments in a dissipative binary collision

    International Nuclear Information System (INIS)

    In the present study, we have tried to estimate the excitation energy of the primary projectile like fragments (PLFs) using the experimental data as well as simulation for the reaction 48Ca + 124Sn at 45 A MeV of lab energy

  20. AB-Net Method of Protection from Projectiles (city, military base, battle-front, etc.)

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The author suggests a low cost special AB-Net from artificial fiber, which may protect cities and important objects from rockets, artillery and mortar shells, projectiles, bullets, and strategic weapons. The idea is as follows: The offered AB-Net joins an incoming projectile to a small braking parachute and this incoming projectile loses speed by air braking after a drag distance of 50 - 150 meters. A following interception net after the first may serve to collect the slowed projectiles and their fragments or bomblets so that they do not reach the aimpoint. The author offers the design of AB-Net, a developed theory of snagging with a small braking parachute by AB-Net; and sample computations. These nets may be used for defense of a town, city, military base, battle-front line, road (from terrorists), or any important objects or installations (for example nuclear electric station, government buildings, etc.). Computed projects are: Net to counter small rockets (for example, from Qassam), net to counter artille...

  1. A heavy ion spectrometer system for the measurement of projectile fragmentation of relativistic heavy ions

    International Nuclear Information System (INIS)

    The Heavy Ion Spectrometer System (HISS) at the LBL Bevalac provided a unique facility for measuring projectile fragmentation cross sections important in deconvolving the Galactic Cosmic Ray (GCR) source composition. The general characteristics of the apparatus specific to this application are described and the main features of the event reconstruction and analysis used in the TRANSPORT experiment are discussed

  2. Breakup of the projectile in heavy ion collisions at intermediate energies

    International Nuclear Information System (INIS)

    Report on an experiment in which the 4He breakup channel of 16O projectiles on various targets (27Al, 58Ni, 197Au) has been studied inclusively, and exclusively (in coincidence with charged pions). The bombarding energy was 94 MeV/nucleon. (D.L.). 7 refs., 5 figs

  3. The Effect of Cooperative Learning on Grade 12 Learners' Performance in Projectile Motions, South Africa

    Science.gov (United States)

    Kibirige, Israel; Lehong, Moyahabo Jeridah

    2016-01-01

    The study explored the effect of cooperative learning on Grade 12 learners' performance in projectile motions. A quasi-experimental research design with non-equivalent control group was used. Two schools were purposively selected from Maleboho Central circuit in South Africa based on their performance in Physical Sciences Grade 12 results of 2011.…

  4. The scaling and dynamics of a projectile obliquely impacting a granular medium.

    Science.gov (United States)

    Wang, Dengming; Ye, Xiaoyan; Zheng, Xiaojing

    2012-01-01

    In this paper, the dynamics of a spherical projectile obliquely impacting into a two-dimensional granular bed is numerically investigated using the discrete element method. The influences of projectile's initial velocities and impacting angles are mainly considered. Numerical results show that the relationship between the final penetration depth and the initial impact velocity is very similar to that in the vertical-impact case. However, the dependence of the stopping time on the impact velocity of the projectile exhibits critical characteristics at different impact angles: the stopping time approximately increases linearly with the impact velocity for small impact angles but decreases in an exponential form for larger impact angles, which demonstrates the existence of two different regimes at low and high impact angles. When the impact angle is regarded as a parametric variable, a phenomenological force model at large impact angles is eventually proposed based on the simulation results, which can accurately describe the nature of the resistance force exerted on the projectile by the granular medium at different impact angels during the whole oblique-impact process. The degenerate model agrees well with the existing experimental results in the vertical-impact cases.

  5. Tissue simulant response at projectile impact on flexible fabric armour systems

    NARCIS (Netherlands)

    Bree, J.L.M.J. van; Volker, A.; Heiden, N. van der

    2006-01-01

    Behind Armour Blunt Trauma is a phenomenon which has been studied extensively for rigid personal protective armour systems. These systems used in e.g. bullet proof vests manage to defeat high velocity small arms projectiles. Tissue simulants are used to study behind armour effects. At high velocity

  6. Wound Ballistics: Study of the Rupture of Human Skin Membrane under the Impact of a Projectile

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1979-07-01

    Full Text Available The paper attempts to theorize the rupture of human skin membrane under the impact of a projectile. An expression for the threshold velocity for penetration has been derived which is found to give results in fair agreement with experimental values reported in literature.

  7. Eulerian simulation of the perforation of aluminum plates by nondeforming projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Silling, S.A.

    1992-03-01

    A new algorithm for the treatment of sliding interfaces between solids with or without friction in an Eulerian wavecode is described. The algorithm has been implemented in the two-dimensional version of the CTH code. The code was used to simulate penetration and perforation of aluminum plates by rigid, conical-nosed tungsten projectiles. Comparison with experimental data is provided.

  8. Resistance and rupture analysis of single- and few-layer graphene nanosheets impacted by various projectiles

    Science.gov (United States)

    Sadeghzadeh, Sadegh; Liu, Ling

    2016-09-01

    In this paper, a quasi-classical model for the collision of various nanoparticles with single- and few-layer graphene nanosheets was introduced as a multi-scale approach that couples non-equilibrium molecular dynamics with the Finite Element Method. As a resistance criterion, it was observed that the coefficient of restitution and the induced stresses depend on the impact velocity of projectile. These parameters were evaluated computationally, and it was revealed that certain resulting behaviors differ from behaviors at the macro scale. By obtaining an out-of-plane yield stress limit of 1.0 TPa for graphene, the stress analysis of single- and multi-layer graphene sheets revealed that the limit projectile velocity needed for the yielding of graphene sheets increases with the increase in the number of layers. For aluminum nanoparticles, this increase is almost linear, and for other metals, it slightly deviates from the linear trend. It was also observed that the graphene sheets have a different rupture form when impacted by gaseous molecules than by metal particles. Considering the very high momentum of gas molecules and their shock-like behavior during high-speed collisions with a graphene sheet, pores with a size of one carbon atom can be created in graphene sheets. Since a single-layer graphene sheet can withstand a projectile which is 3.64 times larger than a projectile impacting a 20-layer graphene sheet, spaced graphene sheets seem to be more effective in absorbing the impact energy of projectiles than conventional few-layer graphene sheets.

  9. Experimental study of the expansion dynamic of 9 mm Parabellum hollow point projectiles in ballistic gelatin.

    Science.gov (United States)

    Bresson, F; Ducouret, J; Peyré, J; Maréchal, C; Delille, R; Colard, T; Demondion, X

    2012-06-10

    We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(®) and Speer Gold Dot(®)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance. PMID:22269130

  10. MULTIPLE IONIZATION PROCESS STUDIED WITH COINCIDENCE TECHNIQUE BETWEEN SLOW RECOIL ION AND PROJECTILE ION IN 42 MeV Arq+—Ar COLLISIONS

    Institute of Scientific and Technical Information of China (English)

    T.Tonuma; T.Matsuo; 等

    1990-01-01

    Slow Ar recoil ion Production cross sections by 42 MeV Ar1+(q=4-14) projectiles were measured using a projectile ion-recoilion coincidence technique in order to provide information on mechanisms of multiple ionization of target atome through pure ionization as well as of that accompaied simultaneously with multiple electron loss or capture of projectiles.The present results suggest that inner-shell electron processes caused through electron transfer into projectiles and also electron ionization by projectiles play a key role in the production of multiply charged recoil ions.

  11. INVESTIGATION OF GLASS PLATE FAILURE MECHANISM SUBJECTED TO COPPER AND STEEL PROJECTILE IMPACTS

    Directory of Open Access Journals (Sweden)

    Qasim H. Shah

    2014-05-01

    Full Text Available Normal 0 false false false EN-US JA X-NONE ABSTRACT: A glass plate was subjected to impact by spherical copper and steel projectiles at low velocities. The glass failure features consisted of a central Hertzian cone made up of comminuted glass and a spider web like cracking pattern around the cone with circumferential and radial cracks. The objective of the investigation was to determine if the damage caused by copper projectile impact compared to steel projectile impact was higher for the same kinetic energy (K.E. projectiles and the reason for this phenomenon. For the constant K.E. impact, copper projectile apparently caused higher damage in glass plate. Higher damage was attributed to projectile contact duration and the contact area between the projectile and the glass plate. Finite element analysis using LS-DYNA based upon maximum principal strain failure criterion for laminated glass model was able to predict the failed material under the impact location and the cracking pattern in the glass plate for a biased meshing scheme. Radial cracks in glass target were reported to be 15% higher for copper projectile impact than the steel projectile impact. ABSTRAK: Kepingan kaca dikenakan impak oleh projektil kuprum dan keluli berbentuk sfera pada halaju rendah. Ciri-ciri kegagalan kaca terdiri daripada kon berpusat Hertzian yang melibatkan kaca yang hancur dan corak pecahan berbentuk sesawang lelabah pada keliling kon dengan retakan lilitan dan jejarian. Tujuan penyelidikan adalah untuk menentukan sebab bagaimana  dengan projektil tenaga kinetik yang sama, kerosakan yang diakibatkan oleh impak projektil kuprum berbanding dengan impak projektil keluli adalah lebih tinggi. Untuk impak tenaga kinetik yang malar, projektil kuprum didapati menyebabkan kerosakan yang lebih ke atas kepingan kaca. Kerosakan lebih disebabkan oleh tempoh sentuhan projektil dan kawasan sentuhan di antara projektil dan kepingan kaca. Analisis unsur terhingga menggunakan LS

  12. Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

    CERN Document Server

    Thies, R; Adachi, T; Aksyutina, Y; Alcantara-Núñes, J; Altstadt, S; Alvarez-Pol, H; Ashwood, N; Aumann, T; Avdeichikov, V; Barr, M; Beceiro-Novo, S; Bemmerer, D; Benlliure, J; Bertulani, C A; Boretzky, K; Borge, M J G; Burgunder, G; Caamano, M; Caesar, C; Casarejos, E; Catford, W; Cederkäll, J; Chakraborty, S; Chartier, M; Chulkov, L V; Cortina-Gil, D; Crespo, R; Datta, U; Fernández, P Díaz; Dillmann, I; Elekes, Z; Enders, J; Ershova, O; Estradé, A; Farinon, F; Fraile, L M; Freer, M; Freudenberger, M; Fynbo, H O U; Galaviz, D; Geissel, H; Gernhäuser, R; Göbel, K; Golubev, P; Diaz, D Gonzalez; Hagdahl, J; Heftrich, T; Heil, M; Heine, M; Henriques, A; Holl, M; Ickert, G; Ignatov, A; Jakobsson, B; Johansson, H T; Jonson, B; Kalantar-Nayestanaki, N; Kanungo, R; Kelic-Heil, A; Knöbel, R; Kröll, T; Krücken, R; Kurcewicz, J; Kurz, N; Labiche, M; Langer, C; Bleis, T Le; Lemmon, R; Lepyoshkina, O; Lindberg, S; Machado, J; Marganiec, J; Maroussov, V; Mostazo, M; Movsesyan, A; Najafi, A; Nilsson, T; Nociforo, C; Panin, V; Paschalis, S; Perea, A; Petri, M; Pietri, S; Plag, R; Prochazka, A; Rahaman, A; Rastrepina, G; Reifarth, R; Ribeiro, G; Ricciardi, M V; Rigollet, C; Riisager, K; Röder, M; Rossi, D; del Rio, J Sanchez; Savran, D; Scheit, H; Simon, H; Sorlin, O; Stoica, V; Streicher, B; Taylor, J T; Tengblad, O; Terashima, S; Togano, Y; Uberseder, E; Van de Walle, J; Velho, P; Volkov, V; Wagner, A; Wamers, F; Weick, H; Weigand, M; Wheldon, C; Wilson, G; Wimmer, C; Winfield, J S; Woods, P; Yakorev, D; Zhukov, M V; Zilges, A; Zuber, K

    2016-01-01

    Background: Models describing nuclear fragmentation and fragmentation-fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool to reach the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from 10,12-18C and 10-15B isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent dataset. We compare our data to model calculations. Results: One-proton removal cross sec...

  13. Experimental and Numerical Correlation of Impact of Spherical Projectile for Damage Analysis of Aero Engine Component

    Directory of Open Access Journals (Sweden)

    Anuradha Nayak Majila

    2016-03-01

    Full Text Available Studies the impact response of flat Titanium alloy plate against spherical projectile for damage analysis of aero engine components using experimental and finite element techniques. Compressed gas gun has been used to impart speed to spherical projectile at various impact velocities for damage studies. Crater dimensions (diameter and depth obtained due to impact have been compared with finite element results using commercially available explicit finite element method code LS-DYNA. Strain hardening, high strain rate and thermal softening effect along with damage parameters have been considered using modified Johnson-Cook material model of LS-DYNA. Metallographic analysis has been performed on the indented specimen. This analysis is useful to study failure analysis of gas turbine engine components subjected to domestic object damage of gas turbine engine. Defence Science Journal, Vol. 66, No. 2, March 2016, pp. 193-199, DOI: http://dx.doi.org/10.14429/dsj.66.9130

  14. Statistical fragmentation of Au projectiles at E/A=600 MeV

    International Nuclear Information System (INIS)

    The mean multiplicity of intermediate mass fragments (MIMF) produced by fragmentation of Au projectiles interacting with targets of C, Al, Cu and Pb at an incident energy of E/A = 600 MeV is compared to predictions of statistical multifragmentation and sequential evaporation models. The initial conditions for the calculations were provided by BUU simulations. In the high excitation energy regime the observed universal correlation between (MIMF) and the total charge Zbound of projectile fragments with charges Z ≥ 2 can not be reprocuced by the sequential evaporation code GEMINI. The data are well described by statistical decay calculations which assume the formation of an expanded nuclear system and a rather fast break-up. (orig.)

  15. An approach for considering ionization of light atoms by relativistic projectiles generating strong electromagnetic fields

    International Nuclear Information System (INIS)

    We propose an approach to treat ionization of light atoms in relativistic collisions with highly charged ions, where the electromagnetic field generated by the ions can be very strong. The approach is based on the observation that, for a collision with a certain momentum transfer, either the relativistic effects, connected with the collision velocity approaching the speed of light, or the higher-order terms in the corresponding Born series in the projectile-target interaction can be of importance for the ionization process. The approach consists of dividing all collisions into those with 'small' and 'large' momentum transfers, which are described by (the first order of) the relativistic Born and the Glauber approximations, respectively. The approach is applied to describe helium single ionization by 1 GeV u-1 U92+ projectiles

  16. Projectile charge and velocity effect on UO2 sputtering in the nuclear stopping regime

    International Nuclear Information System (INIS)

    Angular distributions and yields of uranium sputtered by slow highly charged Xeq+ ions (kinetic energy 1.5 keV ≤ Ek ≤ 81 keV, charge state 1 ≤ q ≤ 25 ) from UO2 were measured by means of the catcher technique. A charge state effect on the sputtering process is observed at 8 and 81 keV. A deviation from a A*cos(θ) shape (the linear collision cascade theory) is observed in case of Xeq+ impinging a UO2 surface at Ek = 8 keV. Yields increase linearly with projectile charge state q thus clearly revealing the contribution of potential energy to the sputtering process. In addition, as the kinetic energy of a Xe10+ projectile decreases from 81 keV to 1.5 keV, a velocity effect is clearly observed on the angular distribution. (authors)

  17. Excitation and decay of projectile-like fragments formed in dissipative peripheral collisions at intermediate energies

    CERN Document Server

    Yañez, R; Alfaro, R; Davin, B; Larochelle, Y; Xu, H; Beaulieu, L; Lefort, T; Viola, V E; De Souza, R T; Liu, T X; Liu, X D; Lynch, W G; Shomin, R; Tan, W P; Tsang, M B; Molen, A V; Wagner, A; Xi Hong Fei; Charity, R J; Sobotka, L G

    2003-01-01

    Projectile-like fragments (PLF:15<=Z<=46) formed in peripheral and mid-peripheral collisions of 114Cd projectiles with 92Mo nuclei at E/A=50 MeV have been detected at very forward angles, 2.1 deg.<=theta_lab<=4.2 deg. Calorimetric analysis of the charged particles observed in coincidence with the PLF reveals that the excitation of the primary PLF is strongly related to its velocity damping. Furthermore, for a given V_PLF*, its excitation is not related to its size, Z_PLF*. For the largest velocity damping, the excitation energy attained is large, approximately commensurate with a system at the limiting temperature

  18. Electron-hydrogen collisions with dressed target and Volkov projectile states in a laser field

    International Nuclear Information System (INIS)

    Cross sections for the 1S-2S and 1S-2PO transitions in laser-assisted e--H(1S) collisions are calculated in both the multi-channel eikonal treatment and the Born wave approximation, as a function of impact energy and laser field intensity. The laser considered is a monotonic, plane-polarized CO2 laser (photon energy = 0.117 eV) with the polarization direction parallel to the initial projectile velocity. The first part of this paper confines the laser perturbation to the bound electrons of the atom. The second part extends the laser perturbation to the projectile electron, and the familiar Volkov dressed states are used. (author)

  19. A NASTRAN investigation of simulated projectile damage effects on a UH-1B tail boom model

    Science.gov (United States)

    Futterer, A. T.

    1980-01-01

    A NASTRAN model of a UH-1B tail boom that had been designed for another project was used to investigate the effect on structural integrity of simulated projectile damage. Elements representing skin, and sections of stringers, longerons and bulkheads were systematically deleted to represent projectile damage. The structure was loaded in a manner to represent the flight loads that would be imposed on the tail boom at a 130 knot cruise. The deflection of four points on the rear of the tail boom relative to the position of these points for the unloaded, undamaged condition of the tail boom was used as a measure of the loss of structural rigidity. The same procedure was then used with the material properties of the aluminum alloys replaced with the material properties of T300/5208 high strength graphite/epoxy fibrous composite material, (0, + or - 45, 90)s for the skin and (0, + or - 45)s for the longerons, stringers, and bulk heads.

  20. Production of helium projectile fragments in 16O-emulsion interactions at 4.5 A GeV/c

    Institute of Scientific and Technical Information of China (English)

    Zhang Dong-Hai; Li Zhen-Yu; Li Jun-Sheng; Wu Feng-Juan

    2004-01-01

    The measurements of partial production cross sections of the multiple helium projectile fragments emitted at 4.5A GeV/c 16O-Em interactions are reported. We have studied the production rate of helium projectile fragments due to fragmentation of 16O ions and compared it with that obtained from different projectiles at various energies. The dependence of on the mass number of the incident beams is formulated. The multiplicity distributions of the helium fragments produced in 16O-Em interactions at different energies exhibit Koba-Nielson-Olesen (KNO) scaling.The correlation of helium projectile fragments and target fragments is also investigated and it is found that the average of target fragments is increased with the decrease of the number of helium fragments in peripheral interactions.

  1. Devices for launching 0.1-g projectiles to 150 km/s or more to initiate fusion. Pt. 2

    International Nuclear Information System (INIS)

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is explored. The analysis reveals that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, a single- and multistage accelerator was designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities. (orig.)

  2. Study on Visual Simulation of Terminal-Sensitive Projectile%末敏弹的可视化仿真研究

    Institute of Scientific and Technical Information of China (English)

    邱荷; 刘荣忠; 郭锐; 张俊

    2013-01-01

    Study on the visualization of tracking and control of Terminal-sensitive Projectile in motion. Because terminal-sensitive projectile will open its parachute and wing during the movement, and its law of motion of the external ballistics are very different from conventional guided missiles, so there are some difficulties to construct its visual simulation test platform. According to the structure characteristics of typical terminal-sensitive projectile and movement characteristics of the deceleration and rotary stage, this paper presented a method of visual simulation using Sim-ulink/Matlab and VR technology. The simulation results have shown that the model of visual simulation system built by using this method is accurate, the scene is vivid, and the system has good characteristics of real—time and controllability. The motion process of the stage of deceleration and rotary is reproduced well, and the result can provide some technical support for development and tactical training of terminal—sensitive projectile.%研究末敏弹运动的实时跟踪与控制问题.因为末敏弹在运动过程中要打开减速伞与减旋翼,外弹道运动规律与常规制导导弹有很大的不同,因此构建末敏弹可视化仿真试验平台有一定的难度.根据典型末敏弹的结构特点及减速减旋段的运动特性,提出了一种利用Simulink/Matlab和VR技术对其进行可视化仿真研究的方法.仿真结果表明,利用上述方法建立的可视化仿真系统模型准确,三维视景逼真,并具有良好的实时性和可控性,很好地再现了末敏弹减速减旋段运动过程,可以为末敏弹的研制和战术训练提供技术支持.

  3. Recent Precision Experiments with Exotic Nuclei Produced with Uranium Projectiles and Experimental Prospects at Fair

    OpenAIRE

    Geissel H.; Chen L.; Dickel T.; Farinon F.; Dillmann I.; Knöbel R.; Kurcewicz J.; Mukha I.; Münzenberg G.; Nociforo C.; Patyk Z.; Pietri S.; Plass W.R.; Prochazka A.; Scheidenberger C.

    2014-01-01

    Precision experiments with relativistic fragments separated in-flight require special experimentalmethods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the inflight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A·MeV 238U ions were used to...

  4. From boron carbide to glass: Absorption of an elongated high-speed projectile in brittle materials

    Science.gov (United States)

    Rumyantsev, B. V.

    2016-09-01

    Penetration into boron carbide of an elongated high-speed projectile in the form of a copper jet produced by an explosion of a cumulative charge is studied. The efficiency of absorption of a copper jet in different brittle materials for evaluating their protective ability is compared. Conditions for the absence of the influence of the lateral unloading wave on the penetration zone, which provide the minimum penetration depth, are determined.

  5. Symmetric eikonal model for projectile-electron excitation and loss in relativistic ion-atom collisions

    OpenAIRE

    Voitkiv, A. B.; Najjari, B.; Shevelko, S. P.

    2010-01-01

    At impact energies $ \\stackrel{>}{\\sim}1$ GeV/u the projectile-electron excitation and loss occurring in collisions between highly charged ions and neutral atoms is already strongly influenced by the presence of atomic electrons. In order to treat these processes in collisions with heavy atoms we generalize the symmetric eikonal model, used earlier for considerations of electron transitions in ion-atom collisions within the scope of a three-body Coulomb problem. We show that at asymptotically...

  6. A Physical Model of Electromagnetic Force from PEMA Acted on Metal Projectiles

    Institute of Scientific and Technical Information of China (English)

    HU Jin-suo; YANG Zuo-bin

    2007-01-01

    Electromagnetic armor is a new conceptual combat vehicle technology, which improves remarkably the defensive capability and maneuverability of vehicles. The authors present definitely to apply the electromagnetic theory to analyze the electromagnetic armor. Based on electromagnetics, the experienced expression of projectile and the physical model of PEMA (passive electromagnetic armor) are obtained when electric current flows through the system, and a computer simulation is given.

  7. INTERACTION MEAN FREE PATH OF He PROJECTILE FRAGMENTS FROM 16O-EM COLLISION AT 60 A GeV

    Institute of Scientific and Technical Information of China (English)

    ZHANG DONG-HA1; SUN HAN-CHENG; G.GHARIBI

    2001-01-01

    The interaction mean free path of He projectile fragments, produced by the collisions of 16O at 60 A GeV in a nuclear emulsion, has been investigated. In the present analysis, 1555 He projectile fragments, giving rise to 320 secondary interactions, have been used. At a level of 3% a very weak signal of anomalons is observed, which comes mainly from the 3×He channel.

  8. Hypervelocity projectile acceleration with a railgun using a two-stage gas gun injector

    Science.gov (United States)

    Hawke, R. S.

    1989-04-01

    Unique potential applications of electromagnetic railguns [R.S. Hawke, IEEE Trans. Nucl. NS-28 (2) (1981) 1542] have motivated a decade of continuous development throughout the world. This effort has led to routine acceleration of projectiles of from 1 g to about 1 kg, to velocities of nearly 4 km/s. Attempts to reach higher velocities have met with problems in the 6- to 8-km/s range [J.V. Parker, Proc. 4th Symp. on Electromagnetic Launch Tech., Austin, TX, 1988, to be published in IEEE Trans. Mag.]. The principal problem is "restrike", which causes shunting of the propulsive plasma armature by the formation of a second plasma short circuit in the breech region of the railgun. One means of impeding restrike is the use of a two-stage light-gas gun (2SLGG) as a projectile injector. A joint development project was initiated in early 1986 between the Sandia National Laboratories Albuquerque (SNLA) and the Lawrence Livermore National Laboratory (LLNL). The project is based on the use of a 2SLGG to inject projectiles at about 7 km/s. The injection gas is hydrogen, which serves to inhibit formation of the secondary arc and to minimize barrel ablation and armature contamination. Results and status of this work are discussed.

  9. Influence of impact conditions on plasma generation during hypervelocity impact by aluminum projectile

    Science.gov (United States)

    Song, Weidong; Lv, Yangtao; Li, Jianqiao; Wang, Cheng; Ning, Jianguo

    2016-07-01

    For describing hypervelocity impact (relative low-speed as related to space debris and much lower than travelling speed of meteoroids) phenomenon associated with plasma generation, a self-developed 3D code was advanced to numerically simulate projectiles impacting on a rigid wall. The numerical results were combined with a new ionization model which was developed in an early study to calculate the ionized materials during the impact. The calculated results of ionization were compared with the empirical formulas concluded by experiments in references and a good agreement was obtained. Then based on the reliable 3D numerical code, a series of impacts with different projectile configurations were simulated to investigate the influence of impact conditions on hypervelocity impact generated plasma. It was found that the form of empirical formula needed to be modified. A new empirical formula with a critical impact velocity was advanced to describe the velocity dependence of plasma generation and the parameters of the modified formula were ensured by the comparison between the numerical predictions and the empirical formulas. For different projectile configurations, the changes of plasma charges with time are different but the integrals of charges on time almost stayed in the same level.

  10. Systematic model-dependent behaviour of fusion involving weakly bound projectiles 6,7Li

    International Nuclear Information System (INIS)

    Many measurements on complete fusion (CF) cross section at above barrier energies involving weakly bound stable projectiles (e.g., 6Li, 7Li and 9Be) show suppression by various degrees compared to theoretical estimates as well as experimental CF cross sections of reactions involving strongly bound projectiles. However, there is no concrete picture at sub-barrier energies. The conclusions based on coupled-channels (CC) calculations using different codes (e.g., FRESCO or CCFULL) may differ as the theoretical models used to calculate fusion are not same. In a recent paper on complete fusion in 7Li+152Sm system, the fusion cross sections calculated by CCFULL and FRESCO have been shown to be different despite using same bare potential. It was observed that with the inclusion of only inelastic couplings, the results of FRESCO were much closer to the experimental data in the above barrier region, while the CCFULL results overpredict the data over the entire range. To explore the above observation in different systems involving 6,7Li as projectile, in the present work, a systematic and detailed study has been carried out by means of CC calculations using both FRESCO and CCFULL. The aim is to analyze the differences between the two models of calculations

  11. The study of quasi-projectiles produced in Ni+Ni and Ni+Au collisions: excitation energy and spin

    International Nuclear Information System (INIS)

    During the collision between the projectile and the target nuclei in the intermediate energy regime (E < 100 MeV/nucleon) two excited nuclei are mainly observed in the exit channel, the quasi projectile (QP) and the quasi target. They disintegrate by particle emission. However, this binary picture is perturbed by the emission of particles and light fragments with velocities intermediate between the projectile velocity and the target one, all along the interaction (midrapidity component). This work aim to determine the excitation energy and the intrinsic angular momentum (or spin) of quasi-projectiles produced in the Ni+Ni and Ni+Au collisions at 52 and 90 MeV/nucleon. The excitation energy is deduced from the kinematical characteristics of particles emitted by the quasi-projectile. They have to be separated from midrapidity particles. Three different scenarios have been used for this purpose. The spin of the quasi-projectile has been extracted from the experimental data by mean of proton and alpha particles multiplicities emitted by the QP in the Ni+Au at 52 MeV/nucleon reaction. The results have been compared to the predictions of a theoretical model based on nucleon transfers. Their evolution is qualitatively reproduced as a function of the violence of the collision. (author)

  12. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    International Nuclear Information System (INIS)

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges

  13. Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; DePiero, A H; Garza, R G; Tarver, C M

    1999-06-01

    Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges.

  14. The motion of an arbitrarily rotating spherical projectile and its application to ball games

    International Nuclear Information System (INIS)

    In this paper the differential equations which govern the motion of a spherical projectile rotating about an arbitrary axis in the presence of an arbitrary ‘wind’ are developed. Three forces are assumed to act on the projectile: (i) gravity, (ii) a drag force proportional to the square of the projectile's velocity and in the opposite direction to this velocity and (iii) a lift or ‘Magnus’ force also assumed to be proportional to the square of the projectile's velocity and in a direction perpendicular to both this velocity and the angular velocity vector of the projectile. The problem has been coded in Matlab and some illustrative model trajectories are presented for ‘ball-games’, specifically golf and cricket, although the equations could equally well be applied to other ball-games such as tennis, soccer or baseball. Spin about an arbitrary axis allows for the treatment of situations where, for example, the spin has a component about the direction of travel. In the case of a cricket ball the subtle behaviour of so-called ‘drift’, particularly ‘late drift’, and also ‘dip’, which may be produced by a slow bowler's off or leg-spin, are investigated. It is found that the trajectories obtained are broadly in accord with those observed in practice. We envisage that this paper may be useful in two ways: (i) for its inherent scientific value as, to the best of our knowledge, the fundamental equations derived here have not appeared in the literature and (ii) in cultivating student interest in the numerical solution of differential equations, since so many of them actively participate in ball-games, and they will be able to compare their own practical experience with the overall trends indicated by the numerical results. As the paper presents equations which can be further extended, it may be of interest to research workers. However, since only the most basic principles of fundamental mechanics are employed, it should be well within the grasp of first

  15. An Example For The Effect of 5E Model on The Academic Success and Attitude of Students: “Projectile Motion”

    Directory of Open Access Journals (Sweden)

    İsmet ERGİN

    2006-12-01

    Full Text Available In this research; during the Physics Education course in GATA Medical Noncommissioned Officer Preparatory School’s first grade, Projectile Motion has been applied to the students with the fundamental principles of 5E Model and the effectiveness of the Physics Education course on academic success and attitudes of the students has been searched. Morever, after presenting the outcomes, some suggestions have been presented. While chosing the course subject, since, the students to whom the course subject has been applied are cadets, Projectile Motion subjects are chosen since they are both complex and interesting. The researh has been carried out with 84 students who were in GATA Medical Noncommissioned Officer Preparatory School’s First Grade. In the researh, multiple choicesuccess tests have been applied for each subject. In the analysis made after the application, It has been observed that the experiment group students to when the 5E Model has been applied react much more beneficial attitudes and are more successful than the control group students to whom the tradetional teaching method has been applied. Some suggestions have been presented by the help of the outcomes that were gained after the researh.

  16. Inner-shell ionization of heavy atoms by slow ions. A study of electronic relativistic effects and projectile Coulomb deflection in the Semiclassical Approximation

    International Nuclear Information System (INIS)

    Several investigations have been made on K and L shell ionization of the heavy collision partner in slow asymmetric collisions based on the SCA. The use of the SCA can only be defended for slow collisions if the projectile has a charge much less than the target. Thus this approximation should first be tested for proton impact on very heavy target elements. For these elements the inner shell electrons move sufficiently fast for a relativistic description to be mandatory. These relativistic effects are in themselves of some interest, as they can be quite large. After discussion of the formulation of the SCA used throughout this work, a further introduction is given on relativistic effects in Coulomb ionisation. Two papers on electronic relativistic effects in K and L shell ionization follow. The next two papers discuss calculations with an exact Coulomb projectile path. The latter of these also touches upon the inclusion of corrections to the SCA from terms beyond first order perturbation theory. In the last paper of this thesis it is shown how the theoretical apparatus developed for the SCA- calculations can immediately be used also for making calculations of more symmetric systems with the Briggs model. Thus, at least for direct ionization in very slow collisions a unification of the SA and MO approaches has apparently been reached. (JIW)

  17. The Chicxulub impact at the K-Pg boundary - search for traces of the projectile

    Science.gov (United States)

    Deutsch, A.

    2012-04-01

    One of the most interesting problems in the context of the end-Cretaceous Chicxulub impact is the question after the whererabouts of the main mass of the projectile. The nature of this >10 km-sized Chicxulub projectile was constrained by an anomaly in the chromium isotope 54 in the K-Pg deposit at Stevens Klint, Denmark, to a carbonaceous chondrite of type CM2 [1]. About 1.5 % of the estimated mass of the projectile has been detected world-wide in the K-Pg boundary layer; mainly in the form of platinum group elements (PGE) as well as other siderophile elements (Ni, Co ... ). A contamination by or even a major contribution of other "projectile" elements to the K-Pg event bed was rarely proposed. The few examples in the literature (cf. compilation in [2, 3]) used rare earth elements (REE) distribution patterns that are slightly inconsistent with REE patterns typical for the upper continental crust (UCC). Ejecta consisting of UCC target rocks is expected to form the overwhelming mass of the ejecta. In most K-Pg layers, however, the ejecta is diluted or even totally masked by a component of more local origin and with features of high-energy deposition mechanisms. Numerical models [4] indicate a deposition of >500km3 projectile material, corresponding to >2 x 10exp9 tons of mainly silica, iron, and magnesium in the K-Pg event bed. Detecting the "meteoritic" origin of these major elements, however, in a matrix of siliceous detritus, is practically impossible. Recent LA-ICP-MS analyses show that siliceous impact spherules - hydrated glass or altered to chlorite - in the Chicxulub event bed at various locations (e.g., Shell Creek, La Lajilla, La Popa) have REE patterns that are flat and un-fractionated, corresponding quite well to a typical CI-pattern. The REE abundances are chondritic to sub-chondritic. Mixing calculations indicate that the maximum REE contribution of UCC material to the REE budget of these spherules is on the order of 2 %, but usually much less. These

  18. Research on Debris Transport Character in Penetrating Channel under Multi-projectiles Repetitive Explosion%多弹重复爆炸下侵彻通道内碎屑运移特性研究

    Institute of Scientific and Technical Information of China (English)

    刘彩花; 焦国太; 韩晶; 张世豪

    2014-01-01

    为了增加钻地武器的侵彻深度,提出一种“串联式”多弹连续爆炸作用方式。在单发弹静爆试验的基础上,拟合出多弹爆炸的周期性爆炸荷载曲线。通过FLUENT软件与EDEM软件耦合数值模拟可知,侵彻通道深度1m时周期性爆炸荷载作用下碎屑的运移能力得到增强,同时进一步研究了介质碎屑运移特性的影响因素。仿真结果表明:介质碎屑的运移能力与爆炸荷载峰值成正比,与碎屑粒径及弹体偏离钻地通道轴线距离成反比。%In order to increase the penetration depth of weapons,a new scheme of tandem multi-projectile contin-uous explosion was put forward. Based on static explosion test of single projectile,the periodical explosion load curve of multi-projectile explosion was also fitted. Through the coupling numerical simulation by the software FLUENT with EDEM,within 1m deep penetrating channels,the debris transport capability was enhanced under continuous explo-sion load. In addition,the influence factors of debris transport character was discussed. Results showed that debris transport capability was proportional to the peak value of explosion load,and inversely proportional to debris particle size and the offset distance of projectile and penetrating channel.

  19. Singly and Doubly Charged Projectile Fragments in Nucleus-Emulsion Collisions at Dubna Energy in the Framework of the Multi-Source Model

    Institute of Scientific and Technical Information of China (English)

    WANG Er-Qin; LIU Fu-Hu; Magda A.Rahim; S.Fakhraddin; SUN Jian-Xin

    2011-01-01

    @@ The multiplicity distributions of projectile fragments emitted in interactions of different nuclei with emulsion are studied by using a multi-source model.Our calculated results show that the projectile fragments can be described by the model and each source contributes an exponential distribution.As the weighted sum of the folding result of many exponential distributions,a multi-component Erlang distribution is used to describe the experimental data.The relationship between the height(or width)of the distribution and the mass of the incident projectile,as well as the dependence of projectile fragments on target groups,are investigated too.

  20. Exact second Born calculations for electron capture for systems with various projectile and target charges

    International Nuclear Information System (INIS)

    Results of exact numerical calculations of differential and total 1s-1s electron-capture cross sections evaluated in the second Born approximation are presented for targets and projectiles of various charges Z/sub T/ and Z/sub P/ at velocities between 10 and 200 MeV/amu. For symmetric systems with Z/sub P/ = Z/sub T/ = Z the Thomas peak in the differential cross section, characteristic of a free-wave second Born-approximation process, appears at velocities above Z2 x (5 MeV/amu), where Z is the nuclear charge of the target (or projectile). The shape of this Thomas peak contains information about real and virtual intermediate states of the system. For total cross sections at velocities below Z2 x (2 MeV) the second Born-approximation cross section is larger than the first Born-approximation cross section indicating a breakdown of the second Born approximation using the free-wave Green's function. Results using the peaking approximation of Drisko converge to our exact second Born-approximation results only at velocities well above Z2 x (10 MeV/amu). For systems asymmetric in Z/sub P/ and Z/sub T/ no exact scaling is found, although the systematics are qualitatively similar to the symmetric case using Z = 1/2(Z/sub P/+Z/sub T/). For p+Ne at 100 MeV, the exact Born-approximation results lie somewhat above exact impulse-approximation calculations. It is found that the peaking approximation of Briggs and Simony converges to exact second Born-approximation results as the asymmetry of the projectile and target charges increases

  1. Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

    Science.gov (United States)

    Thies, R.; Heinz, A.; Adachi, T.; Aksyutina, Y.; Alcantara-Núñes, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Camaño, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkäll, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Datta, U.; Díaz Fernández, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estradé, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhäuser, R.; Göbel, K.; Golubev, P.; Gonzalez Diaz, D.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Knöbel, R.; Kröll, T.; Krücken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Röder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K.; R3B Collaboration

    2016-05-01

    Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from 10,12 -18C and B-1510 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1 p x n ) for relativistic 10,12 -18C and B-1510 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the epax code is not able to describe the data satisfactorily. Using abrabla07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease abrabla07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study.

  2. Projectile X-ray emission in relativistic ion-atom collisions

    OpenAIRE

    Salem, Shadi

    2010-01-01

    This work reports on the study of the projectile x-ray emission in relativistic ion-atom collisions. Excitation of K-shell in He-like uranium ions, electron capture into H-like uranium ions and Simultaneous ionization and excitation of initially He-like uranium ions have been studied using the experimental storage ring at GSI. Information about the population of the excited states for the H- and He-like uranium ions, can be obtained by measuring the angular distribution of the decay radiation...

  3. Maximum range of a projectile thrown from constant-speed circular motion

    CERN Document Server

    Poljak, Nikola

    2016-01-01

    The problem of determining the angle at which a point mass launched from ground level with a given speed is a standard exercise in mechanics. Similar, yet conceptually and calculationally more difficult problems have been suggested to improve student proficiency in projectile motion. The problem of determining the maximum distance of a rock thrown from a rotating arm motion is presented and analyzed in detail in this text. The calculational results confirm several conceptually derived conclusions regarding the initial throw position and provide some details on the angles and the way of throwing (underhand or overhand) which produce the maximum throw distance.

  4. Numerical-analytical Algorithm for Constructing the Envelope of the Projectile Trajectories in Midair

    CERN Document Server

    Chudinov, Peter S

    2009-01-01

    A classic problem of the motion of a point mass (projectile) thrown at an angle to the horizon is reviewed. The air drag force is taken into account with the drag factor assumed to be constant. An analytic approach is mainly used for the investigation. Simple analytical formulas are used for the constructing the envelope of the family of the point mass trajectories. The equation of envelope is applied for the determination of the maximum range of flight. The motion of a baseball is presented as an example.

  5. Nuclear Matter Incompressibility Effect on the Cross Section of Fusion Reactions with a weakly bound projectile

    CERN Document Server

    Seyyedi, S A

    2015-01-01

    Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be +209Bi,208Pb,29Si and 27Al reactions. The results show that applying these effects at energies near the Coulomb barrier improves the agreement between the calculated and experimental cross sections, and modifies the mean values of the suppression parameter.

  6. Maximum range of a projectile launched from a height h: a non-calculus treatment

    International Nuclear Information System (INIS)

    The classical example of problem solving, maximizing the range of a projectile launched from height h with velocity v over the ground level, has received various solutions. In some of these, one can find the maximization of the range R by differentiating R as a function of an independent variable or through the implicit differentiation in Cartesian or polar coordinates. In other papers, various elegant non-calculus solutions can be found. In this paper, this problem is revisited on the basis of the elementary analytical geometry and the trigonometry only. (papers)

  7. Computerized System for Evaluating Small Arm Projectile Trajectory Parameters Involving Space Time Functions

    Directory of Open Access Journals (Sweden)

    M. Jauhari

    1982-07-01

    Full Text Available Evaluation of certain parameters of the trajectory of a small arm projectile on the basis of Siacci approximation requires the values of space (S and Time (T functions as tabulated in the Ingalls and Hodsock ballistic tables. The development is reported of a computerized system, whereby the necessity of referring to these tables has been completely obviated. Programme flow-char has been presented and the logic behind the flow of programme has been made explicit. The programme has been executed successfully on the DCM Microsystem 1121.

  8. Some physical magnitudes of interest for nuclear reactions and their dependence on the projectile-target system

    International Nuclear Information System (INIS)

    The design and analysis of experiences with heavy ions requires the knwoledge of several characteristic parameters of the collision and their dependence on the reactant system. In the case of an electrostatic accelerator as the TANDAR, the bombarding energy (function of the projectile) is a direct consequence of the evolution of the charged state distribution for the projectile at the exit of the last stripper, as a function of the atomic number. The complexity resulting from this dependence originated the confection of a series of diagrams. The diagrams correpond to the different physical magnitudes of interest in the analysis of nuclear reactions as a function of the projectile-target combination for terminal tensions similar to those expected to reach at the TANDAR. In each case, the curves are refered to the following physical magnitudes: Ecm/Bc Kinetic energy in the center of the mass system and Coulomb barrier for the projectile-target system, Lgr = angular momentum corresponding to the grazing collisions. Diagrams of the average projectile energy per nucleon for the different values of the terminal tensions with one or two solid strippers are included. The use of the diagrams in some practical applications is illustrated through four examples. The diagrams may be extended, if necesary, to other physical magnitudes, at different accelerator's operating conditions. (M.E.L.)

  9. Fusion with projectiles form carbon to argon at energies between 20A and 60A MeV

    International Nuclear Information System (INIS)

    A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MEV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behaviour. Finally, the decay of highly excited (E* approximately 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

  10. Experimental and theoretical results on electron emission in collisions between He targets and dressed Liq+ (q = 1, 2) projectiles

    International Nuclear Information System (INIS)

    We investigate experimentally and theoretically the electron emission in collisions between He atoms and Liq+ (q = 1, 2) projectiles at intermediate to high incident energies. We report on measured absolute values of double-differential cross-sections, as a function of the emitted electron energy and angle, at a collision energy of 440 keV u−1. The different contributions from target ionization, projectile ionization, and simultaneous target–projectile ionization are calculated with the quantum-mechanical continuum distorted wave and continuum distorted wave–eikonal initial state models, and with classical trajectory Monte Carlo simulations. There is an overall good agreement of the calculations with the experimental data for electron emission cross-sections. (paper)

  11. Experimental and theoretical results on electron emission in collisions between He targets and dressed Liq+ (q = 1, 2) projectiles

    Science.gov (United States)

    Fregenal, D.; Monti, J. M.; Fiol, J.; Fainstein, P. D.; Rivarola, R. D.; Bernardi, G.; Suárez, S.

    2014-08-01

    We investigate experimentally and theoretically the electron emission in collisions between He atoms and L{{i}^{q+}} (q = 1, 2) projectiles at intermediate to high incident energies. We report on measured absolute values of double-differential cross-sections, as a function of the emitted electron energy and angle, at a collision energy of 440 keV u-1. The different contributions from target ionization, projectile ionization, and simultaneous target-projectile ionization are calculated with the quantum-mechanical continuum distorted wave and continuum distorted wave-eikonal initial state models, and with classical trajectory Monte Carlo simulations. There is an overall good agreement of the calculations with the experimental data for electron emission cross-sections.

  12. Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions of He+ with noble gases

    International Nuclear Information System (INIS)

    Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions between He+ ions and noble gases have been measured for energies between 1.0 and 3.5 MeV. The data have been compared with other absolute cross sections that exist in the literature for the same projectile, and with calculations for the screening mode (nucleus-electron interaction) using both perturbative (plane-wave Born approximation (PWBA)) and non-perturbative (extended classical-impulse free-collision model, sudden approximation and coupled-channel method) approaches, and for the antiscreening mode (electron-electron interaction) within the PWBA. The energy dependence of the average number of active electrons for the antiscreening has been described by means of a simple function, which is 'universal' for noble gases but projectile dependent. A previously developed method has been employed to obtain the number of active electrons for each target subshell in the high-velocity regime.

  13. Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions of He+ with noble gases

    Science.gov (United States)

    Santos, A. C. F.; Sigaud, G. M.; Melo, W. S.; Sant'Anna, M. M.; Montenegro, E. C.

    2011-02-01

    Absolute cross sections for projectile electron loss accompanied by target multiple ionization in collisions between He+ ions and noble gases have been measured for energies between 1.0 and 3.5 MeV. The data have been compared with other absolute cross sections that exist in the literature for the same projectile, and with calculations for the screening mode (nucleus-electron interaction) using both perturbative (plane-wave Born approximation (PWBA)) and non-perturbative (extended classical-impulse free-collision model, sudden approximation and coupled-channel method) approaches, and for the antiscreening mode (electron-electron interaction) within the PWBA. The energy dependence of the average number of active electrons for the antiscreening has been described by means of a simple function, which is 'universal' for noble gases but projectile dependent. A previously developed method has been employed to obtain the number of active electrons for each target subshell in the high-velocity regime.

  14. Projectile fragmentation of 40,48Ca and isotopic scaling in a transport approach

    Science.gov (United States)

    Mikhailova, T. I.; Erdemchimeg, B.; Artukh, A. G.; Di Toro, M.; Wolter, H. H.

    2016-07-01

    We investigate theoretically projectile fragmentation in reactions of 40,48Ca on 9Be and 181Ta targets using a Boltzmann-type transport approach, which is supplemented by a statistical decay code to describe the de-excitation of the hot primary fragments. We determine the thermodynamical properties of the primary fragments and calculate the isotope distributions of the cold final fragments. These describe the data reasonably well. For the pairs of projectiles with different isotopic content we analyze the isotopic scaling (or isoscaling) of the final fragment distributions, which has been used to extract the symmetry energy of the primary source. The calculation exhibits isoscaling behavior for the total yields as do the experiments. We also perform an impact-parameter-dependent isoscaling analysis in view of the fact that the primary systems at different impact parameters have very different properties. Then the isoscaling behavior is less stringent, which we can attribute to specific structure effects of the 40,48Ca pair. The symmetry energy determined in this way depends on these structure effects.

  15. EFFECT OF BODY SHAPE ON THE AERODYNAMICS OF PROJECTILES AT SUPERSONIC SPEEDS

    Directory of Open Access Journals (Sweden)

    ABDULKAREEM SH. MAHDI

    2008-12-01

    Full Text Available An investigation has been made to predict the effects of forebody and afterbody shapes on the aerodynamic characteristics of several projectile bodies at supersonic speeds using analytical methods combined with semi-empirical design curves. The considered projectile bodies had a length-to-diameter ratio of 6.67 and included three variations of forebody shape and three variations of afterbody shape. The results, which are verified by comparison with available experimental data, indicated that the lowest drag was achieved with a cone-cylinder at the considered Mach number range. It is also shown that the drag can be reduced by boattailing the afterbody. The centre-of-pressure assumed a slightly rearward location for the ogive-cylinder configuration when compared to the configuration with boattailed afterbody where it was the most forward. With the exception of the boattailed afterbody, all the bodies indicated inherent static stability above Mach number 2 for a centre-of-gravity location at about 40% from the body nose.

  16. The influence of projectile ion induced chemistry on surface pattern formation

    Science.gov (United States)

    Karmakar, Prasanta; Satpati, Biswarup

    2016-07-01

    We report the critical role of projectile induced chemical inhomogeneity on surface nanostructure formation. Experimental inconsistency is common for low energy ion beam induced nanostructure formation in the presence of uncontrolled and complex contamination. To explore the precise role of contamination on such structure formation during low energy ion bombardment, a simple and clean experimental study is performed by selecting mono-element semiconductors as the target and chemically inert or reactive ion beams as the projectile as well as the source of controlled contamination. It is shown by Atomic Force Microscopy, Cross-sectional Transmission Electron Microscopy, and Electron Energy Loss Spectroscopy measurements that bombardment of nitrogen-like reactive ions on Silicon and Germanium surfaces forms a chemical compound at impact zones. Continuous bombardment of the same ions generates surface instability due to unequal sputtering and non-uniform re-arrangement of the elemental atom and compound. This instability leads to ripple formation during ion bombardment. For Argon-like chemically inert ion bombardment, the chemical inhomogeneity induced boost is absent; as a result, no ripples are observed in the same ion energy and fluence.

  17. Prospects for the discovery of the next new element: Influence of projectiles with Z > 20

    CERN Document Server

    Folden, Charles M; Werke, Tyler A; Alfonso, Marisa C; Bennett, Megan E; DeVanzo, Michael J

    2012-01-01

    The possibility of forming new superheavy elements with projectiles having Z > 20 is discussed. Current research has focused on the fusion of 48Ca with actinides targets, but these reactions cannot be used for new element discoveries in the future due to a lack of available target material. The influence on reaction cross sections of projectiles with Z > 20 have been studied in so-called analog reactions, which utilize lanthanide targets carefully chosen to create compound nuclei with energetics similar to those found in superheavy element production. The reactions 48Ca, 45Sc, 50Ti, 54Cr + 159Tb, 162Dy have been studied at the Cyclotron Institute at Texas A&M University using the Momentum Achromat Recoil Spectrometer. The results of these experimental studies are discussed in terms of the influence of collective enhancements to level density for compound nuclei near closed shells, and the implications for the production of superheavy elements. We have observed no evidence to contradict theoretical predict...

  18. Lithic raw material procurement for projectiles points in the prehistory of Uruguay

    Directory of Open Access Journals (Sweden)

    José María López Mazz

    2015-03-01

    Full Text Available This paper focuses on current research on early colonisation of the Atlantic coast of South America during the early Holocene. We present advances in the investigation of raw material procurement at the Rincón de los Indios site, located in the eastern part of Uruguay. The technological studies suggest that some aspects of different styles of projectile points are related with environmental adaptation processes, experienced by the first American people in the New World. The occupation of new spaces and new forms of exploitation of resources changes the organisation of lithic technology. The distance to good quality rocks were critical for the opportunities and economic organisation of hunting groups. The study of changes in lithic procurement strategies for projectile points helps us develop a more comprehensive knowledge of this important social adaptation process which occurred during this period. These patterns started to become stabilised in the latter part of the early Holocene across the extended territory and confirm the efficient land occupation associated an intensive hunter-gatherer economies.

  19. A STUDY ON THE COUNTER-INTUITIVE BEHAVIORS OF PIN-ENDED BEAMS UNDER PROJECTILE IMPACT

    Institute of Scientific and Technical Information of China (English)

    Li Haiwang; Qin Dongqi

    2006-01-01

    The counter-intuitive behaviors of pin-ended beams under the projectile impact are investigated with ANSYS/LS-DYNA in this paper. It studies in detail their displacement-time history curves, final deformed shapes, energy relationships and projectile impact velocity ranges related to their counterintuitive behaviors. The influences of the impact positions on their counterintuitive behaviors are also discussed. The results show that no matter where the impact position on the beam is, the counter-intuitive behaviors of pinned beams will occur as long as the impacting velocity lies within a proper range. Corresponding to the occurring of the counterintuitive behaviors, the rebounding number in the displacement history curves of the beams decreases from a few times to zero with an increase of the impact velocity. The final deformation modes of the beam corresponding to the counter-intuitive behaviors will appear in symmetrical and unsymmetrical forms no matter where the impact position is; the impact velocity of the first-occurring of the counter-intuitive behaviors of the beam increases slowly with the deviation of the impact position away from the mid-span.

  20. Electron capture by fully stripped high-Z projectiles from the hydrogen atom

    International Nuclear Information System (INIS)

    A single-channel distorted-wave approximation is used to calculate the one-electron capture cross section into an arbitrary state (nlm) of Ti22+, V23+, and Fe26+ from the ground state of a hydrogen atom. Since the interaction between the heavy projectile and the target electron is stronger, we represent the initial-channel wave function by a continuum distorted wave while the wave function in the final channel is taken to be a traveling atomic orbital. The nth partial cross sections are found to be in qualitative agreement with previous calculations for some other systems. It is found that at high energies the value nmax, where the nth partial cross section is maximum, is larger by a few steps than obtained from the nmax=Z3/4 model. However, for a fixed projectile nmax moves towards the smaller values as the energy increases. The l dependence of the cross sections are also studied at different energies at the corresponding nmax. We have further studied the mth partial cross sections at various energies and at the corresponding nmax for several l values. It is found that the contributions from higher m values are decreasing rapidly for m>5

  1. Evaluation of the performance of three elastomers for non-lethal projectile applications

    Science.gov (United States)

    Thota, N.; Epaarachchi, J.; Lau, K. T.

    2015-09-01

    Less lethal kinetic ammunitions with soft noses such as eXact iMpact 1006, National Sports Spartan and B&T have been commonly used by military and law enforcement officers in the situations where lethal force is not warranted. In order to explore new materials to be used as nose in such ammunitions, a scholastic study using finite element simulations has been carried out to evaluate the effectiveness of two rubber like elastomers and a polyolefinic foam (low density, highly compressible, stiff and closed cell type of thermos plastic elastomer). State-of-the art thorax surrogate MTHOTA has been employed for the evaluation of blunt thoracic trauma. Force-rigid wall method was employed for the evaluation of head damage curves for each material. XM 1006 has been used as the benchmark projectile for the purpose of comparison. Both blunt thoracic trauma and head damage criterion point of view, both rubbers (R1 and R2) have yielded high values of VCmax and peak impact force. Polyolefinic foam (F1) considered in the study has yielded very promising VCmax values and very less peak impact force when compared with those of bench mark projectile XM 1006.

  2. Bringing Javanesse Traditional Dance into Basic Physics Class: Exemplifying Projectile Motion through Video Analysis

    Science.gov (United States)

    Handayani, Langlang; Prasetya Aji, Mahardika; Susilo; Marwoto, Putut

    2016-08-01

    An alternative approach of an arts-based instruction for Basic Physics class has been developed through the implementation of video analysis of a Javanesse traditional dance: Bambangan Cakil. A particular movement of the dance -weapon throwing- was analyzed by employing the LoggerPro software package to exemplify projectile motion. The results of analysis indicated that the movement of the thrown weapon in Bambangan Cakil dance provides some helping explanations of several physics concepts of projectile motion: object's path, velocity, and acceleration, in a form of picture, graph and also table. Such kind of weapon path and velocity can be shown via a picture or graph, while such concepts of decreasing velocity in y direction (weapon moving downward and upward) due to acceleration g can be represented through the use of a table. It was concluded that in a Javanesse traditional dance there are many physics concepts which can be explored. The study recommends to bring the traditional dance into a science class which will enable students to get more understanding of both physics concepts and Indonesia cultural heritage.

  3. Classical simulations of heavy-ion fusion reactions and weakly-bound projectile breakup reactions

    Indian Academy of Sciences (India)

    S S Godre

    2014-05-01

    Heavy-ion collision simulations in various classical models are discussed. Heavy-ion reactions with spherical and deformed nuclei are simulated in a classical rigid-body dynamics (CRBD) model which takes into account the reorientation of the deformed projectile. It is found that the barrier parameters depend not only on the initial orientations of the deformed nucleus, but also on the collision energy and the moment of inertia of the deformed nucleus. Maximum reorientation effect occurs at near- and below-barrier energies for light deformed nuclei. Calculated fusion crosssections for 24Mg + 208Pb reaction are compared with a static-barrier-penetration model (SBPM) calculation to see the effect of reorientation. Heavy-ion reactions are also simulated in a 3-stage classical molecular dynamics (3S-CMD) model in which the rigid-body constraints are relaxed when the two nuclei are close to the barrier thus, taking into account all the rotational and vibrational degrees of freedom in the same calculation. This model is extended to simulate heavy-ion reactions such as 6Li + 209Bi involving the weakly-bound projectile considered as a weakly-bound cluster of deuteron and 4He nuclei, thus, simulating a 3-body system in 3S-CMD model. All the essential features of breakup reactions, such as complete fusion, incomplete fusion, no-capture breakup and scattering are demonstrated.

  4. Effects of the projectile electronic structure on Bethe-Bloch stopping parameters for Ag

    Science.gov (United States)

    Moussa, D.; Damache, S.; Ouichaoui, S.

    2010-06-01

    Energy losses of protons and alpha particles in silver have been accurately measured under the same experimental conditions over the velocity range E=(0.192-2.595) MeV/amu using the transmission method. Deduced S(E) stopping powers are compared to most accurate ones from the literature, to values generated by the SRIM-2008 computer code and to ICRU-49 compilation. They were analyzed in the framework of modified Bethe-Bloch theory for extracting Ag target mean excitation and ionization potential, I, and Barkas effect parameter, b. Values of ( 466±5) eV and 1.20±0.01 for these two parameters were inferred from the proton S(E) data while the alpha particle data yielded values of (438±4) eV and 1.38±0.01, respectively. The ( I, b) stopping parameters thus exhibit opposite variations as the projectile charge increases, similarly as we have found previously for nickel [6]. This can be ascribed only to an effect of the projectile electronic structure at low velocities. The obtained results are discussed in comparison to previous ones reported in the literature.

  5. Effects of the projectile electronic structure on stopping parameters for nickel

    Science.gov (United States)

    Damache, S.; Ouichaoui, S.; Moussa, D.; Dib, A.

    2006-08-01

    The stopping powers of nickel foils for 1H+, 2H+ and 4He2+ ions have been accurately measured over the energy range E ≈ (0.166-2.725) MeV/amu. The data were compared to those reported in the literature and to values derived by the SRIM-2003 code. They were analysed in the framework of the modified Bethe-Bloch theory to extract the target mean excitation and ionisation potential, I, and the Barkas effect parameter, b. The values derived from the proton and the alpha particle data are {I = (311.11 ± 2.61) eV, b = 1.38 ± 0.01} and {I = (276.12 ± 2.84) eV, b = 1.58 ± 0.01}, respectively. They thus show opposite variations of the I and b parameters as the projectile charge increases, presumably due only to the incident ions electronic structure. Besides, the reduced stopping power data for incident deuterons show to be fully consistent with those for protons indicating no effect of the projectile isotopic structure on the target stopping parameters. These results are discussed in comparison with ones reported in the literature.

  6. Novel method for the production of spin-aligned RI beams in projectile fragmentation reaction with the dispersion matching technique

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Y., E-mail: yuichikawa@phys.titech.ac.jp [Tokyo Institute of Technology, Department of Physics (Japan); Ueno, H. [RIKEN Nishina Center (Japan); Ishii, Y. [Tokyo Institute of Technology, Department of Physics (Japan); Furukawa, T. [Tokyo Metropolitan University, Department of Physics (Japan); Yoshimi, A. [Okayama University, Research Core for Extreme Quantum World (Japan); Kameda, D.; Watanabe, H.; Aoi, N. [RIKEN Nishina Center (Japan); Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan); Balabanski, D. L. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy (Bulgaria); Chevrier, R.; Daugas, J. M. [CEA, DAM, DIF (France); Fukuda, N. [RIKEN Nishina Center (Japan); Georgiev, G. [CSNSM, IN2P3-CNRS, Universite Paris-sud (France); Hayashi, H.; Iijima, H. [Tokyo Institute of Technology, Department of Physics (Japan); Inabe, N. [RIKEN Nishina Center (Japan); Inoue, T. [Tokyo Institute of Technology, Department of Physics (Japan); Ishihara, M.; Kubo, T. [RIKEN Nishina Center (Japan); and others

    2013-05-15

    A novel method to produce spin-aligned rare-isotope (RI) beam has been developed, that is the two-step projectile fragmentation method with a technique of dispersion matching. The present method was verified in an experiment at the RIKEN RIBF, where an RI beam of {sup 32}Al with spin alignment of 8(1) % was successfully produced from a primary beam of {sup 48}Ca, with {sup 33}Al as an intermediate nucleus. Figure of merit of the present method was found to be improved by a factor larger than 50 compared with a conventional method employing single-step projectile fragmentation.

  7. New approach to the nuclear in beam {gamma} spectroscopy of neutron rich nuclei at N=20 using projectile fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Jimenez, M.J.; Saint-Laurent, M.G.; Achouri, L.; Daugas, J.M. [Grand Accelerateur National d`Ions Lourds, 14 - Caen (France); Belleguic, M.; Azaiez, F.; Bourgeois, C. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Stanoiu, M.; Borcea, C. [Institute of Atomic Physics, Bucharest (Romania); Angelique, J.C. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire] [and others

    1999-11-01

    The structure of nuclei far from stability around {sup 32}Mg have been recently investigated by means of a novel method. In-beam {gamma}-decay spectroscopy of a large number of exotic neutron-rich nuclei produced by projectile fragmentation of a {sup 36}S projectile has been performed, using coincidences between the recoil fragments collected at the focal plane of SPEG spectrometer and {gamma}-rays emitted at the target location. Preliminary results on both the population mechanism and the decay of excited states in nuclei around {sup 32}Mg are presented. (author) 24 refs.

  8. Role of projectile charge state in convoy electron emission by fast protons colliding with LiF(0 0 1)

    Science.gov (United States)

    Aldazabal, I.; Gravielle, M. S.; Miraglia, J. E.; Arnau, A.; Ponce, V. H.

    2005-05-01

    Target ionization and projectile ionization differential cross sections are used to calculate the electron emission spectra by fast proton impact on ionic crystal surfaces under grazing incidence conditions. Both bare protons and neutral hydrogen species are considered. We use a planar potential approach to determine the projectile trajectory that later on allows us to calculate the charge state fractions. We show that, although the fraction of protons is significantly higher, the contribution from neutral hydrogen ionization has to be considered. The energy and angular dependence of the spectra is analyzed.

  9. Measurement Methods for Muzzle-leaving Time of Projectile%弹丸出炮口时间测试方法研究

    Institute of Scientific and Technical Information of China (English)

    王宝元; 钞红晓; 邵小军; 张鹏飞; 曹馨; 洪丽娜

    2012-01-01

    为了用实验测试方法准确得到弹丸出炮口时间参数,以小口径火炮为实验对象,采用高速摄影法、靶丝通断法、光电法和后坐位移法等4种方法,开展弹丸出炮口时刻的时间参数测试方法研究.用4种方法同时测试同一弹丸出炮口时间,用同一台数据采集系统采集4种信号,以高速摄影法得到的时间曲线为时间基准,将4种时间信号统一到相同时间坐标中.高速摄影法测试最直接、数据最可靠.通断靶丝是被高速燃气流吹断的,而不是被弹头碰断的.先于弹丸泄露的火药气体使光电传感器提前触发.%In order to obtain the muzzle-leaving time of projectile accurately, a small caliber gun was taken as tested object, and four methods, such as high-speed photography, on-off target, photoelectric and recoil displacement methods were simultaneously used for the same projectile and a data acquisition system was used to acquire four signals, in order to search the best measurement method. Taken the result obtained by high-speed photography as time benchmark, four signals were unified in the same time coordinate. The results show that the high-speed photography is a direct and reliable method, on-off target is broken by high-speed burning gas flow before the projectile, and the powder gas triggers the photoelectric sensor earlier.

  10. Projectile Impact Location Measurement Based on N Shape Laser Screen%基于N形光幕的弹着点坐标测试方法

    Institute of Scientific and Technical Information of China (English)

    张建平; 刘吉; 张斌; 刘小彦

    2015-01-01

    针对传统的弹着点坐标测试手段需要人工判读、效率低、精度差,现有方法存在结构复杂、稳定差等问题,提出了 N 形光幕弹着点坐标测试的方法。该方法以矩形激光光幕作为模块单元拼接形成大面积 N 型光幕,根据弹丸到达各个光幕的时间及相对几何关系获得 X 方向坐标,采用高速相机成像获取Y 方向坐标。同时可完成弹丸速度参数的测试。理论分析表明,单个模块采用532 nm,20 mW 激光器可满足高速相机灵敏度的需求,理想坐标测试精度可优于±2.5 mm。比对实验表明,反射成像法优于透射成像法,线阵高速相机在行频为200 kHz 时,对4 mm 模拟弹丸可清晰成像。%Aim at disadvantages of traditional impact coordinates test methods such as artificial interpretation, low efficiency,poor precision,and the existing methods were of complex structure,lack of stability,we pro-posed a new method based on the N shape laser screen.This method took rectangular laser screen as a module unit spliced into a large N shape laser screen,obtained the X coordinate according to the time at which the pro-jectile reaches each screen and the relative geometric relationship,achievd the Y coordinate by means of the re-flective imaging of high speed camera.At the same time the velocity measurement of projectile was achieved. The theoretical analysis indicate that by using 532 nm,20 mW laser the demand of the sensitivity of high-speed camera could be met,and the accuracy of ideal coordinate measurement was ± 2.5mm higher.Comparative ex-periments showed that reflective imaging method was better in transmission.When the line frequency of linear speed camera was 200 kHz,it could achieve clear image for simulate projectile whose diameter was 4mm.

  11. Ballistic Impact Response of Ceramic-Faced Aramid Laminated Composites Against 7.62 mm Armour Piercing Projectiles

    Directory of Open Access Journals (Sweden)

    Nityananda Nayak

    2013-07-01

    Full Text Available Ballistic impact response of ceramic- composite armor, consisting of zirconia toughened alumina (ZTA ceramic front and aramid laminated composite as backing, against 7.62 mm armor piercing (AP projectiles has been studied. Two types of backing composite laminates i.e. Twaron-epoxy and Twaron-polypropylene (PP of 10 mm and 15 mm thickness were used with a ceramic face of 4mm thick ZTA. The ceramic- faced and the stand alone composite laminates were subjected to ballistic impact of steel core 7.62 mm AP projectiles with varying impact velocities and their V50 ballistic limit (BL was determined. A sharp rise in BL was observed due to addition of ceramic front layer as compared to stand alone ones. The impact energy was absorbed during penetration primarily by fracture of ceramic, deformation and fracture of projectile and elastic-plastic deformation of flexible backing composite layer. The breaking of ceramic tiles were only limited to impact area and did not spread to whole surface and projectile shattering above BL and blunting on impact below BL was observed. The ceramic- faced composites showed higher BL with Twaron-PP as backing than Twaron-epoxy laminate of same thickness. This combination of ceramic-composite laminates exhibited better multi-hit resistance capability; ideal for light weight armor.Defence Science Journal, 2013, 63(4, pp.369-375, DOI:http://dx.doi.org/10.14429/dsj.63.2616

  12. Ionization of small molecules induced by H+, H e+ , and N+ projectiles: Comparison of experiment with quantum and classical calculations

    Science.gov (United States)

    Kovács, S. T. S.; Herczku, P.; Juhász, Z.; Sarkadi, L.; Gulyás, L.; Sulik, B.

    2016-07-01

    We report the energy and angular distribution of ejected electrons from C H4 and H2O molecules impacted by 1 MeV H+, H e+ , and 650 keV N+ ions. Spectra were measured at different observation angles, from 2 to 2000 eV. The obtained absolute double-differential electron-emission cross sections (DDCSs) were compared with the results of classical trajectory Monte Carlo (CTMC) and continuum distorted wave, eikonal initial state (CDW-EIS) calculations. For the bare H+ projectile both theories show remarkable agreement with the experiment at all observed angles and energies. The CTMC results are in similarly good agreement with the DDCS spectra obtained for impact by dressed H e+ and N+ ions, where screening effects and electron loss from the projectile gain importance. The CDW-EIS calculations slightly overestimate the electron loss for 1 MeV H e+ impact, and overestimate both the target and projectile ionization at low emitted electron energies for 650 keV N+ impact. The contribution of multiple electron scattering by the projectile and target centers (Fermi shuttle) dominates the N+-impact spectra at higher electron energies, and it is well reproduced by the nonperturbative CTMC calculations. The contributions of different processes in medium-velocity collisions of dressed ions with molecules are determined.

  13. Behaviour of Thin Aluminium Plates Subjected to Impact by Ogive-nosed Projectiles

    Directory of Open Access Journals (Sweden)

    M.A. Iqbal

    2006-11-01

    Full Text Available A pneumatic gas gun has been used to fire ogive-nosed projectiles on aluminium plates(1mm at varying impact velocities above the ballistic limit. Impact and residual velocities havebeen measured. Deformation of the target plate was studied. Experimental results formed thebasis of a subsequent finite element analysis of the problem using the ABAQUS 6.3 code. TheJohnson-Cook plastic flow and fracture model available in the code were utilised. Explicit finiteelement analysis has been performed to model the perforation phenomenon. Numerical resultswere significantly improved by reducing the element size up to a certain level beyond which nosignificant variation in the results was observed. Adaptive meshing has been found to be usefulin obtaining the accurate results and avoiding the problem of premature termination of theprogram due to excessive element distortion. Experimental and numerical results are comparedand a good agreement between the two has been found.

  14. Multiple-laser flash shadowgraphy system for terminal studies of small-caliber projectiles

    Science.gov (United States)

    Kalonia, R. C.; Mitra, Gautam; Singh, G. S.; Varma, R. K.; Singh, Manpreet; Singh, Manjit; Sethi, V. S.; Yadav, M. S.

    2010-06-01

    A multiple-laser flash shadowgraphy system has been innovatively designed and developed to study the terminal effects of projectiles. The system has been designed based on modulated laser diodes operated at low voltage and current. In order to study the ballistics effects of small arms, an exposure time of the order of a few hundreds ns and a delay time of the order of a few tens of μs are needed. An ultrashort pulse generator has been developed to provide the exposure and delay time pulses. The developed system has been integrated with a field lens assembly and camera assembly. To record the shadowgraphs, a target is placed near the center of the field lens and a bullet is fired from a fixed gun. The system is described, and experimental results and conclusions are reported.

  15. Total Fragmentation Cross Section of 158A GeV Lead Projectiles in Cu Target

    Institute of Scientific and Technical Information of China (English)

    Mukhtar Ahmed Rana; Shahid Manzoor

    2008-01-01

    Total fragmentation cross section for the reaction 158A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A Pb projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region (63 ≤Z≤83) are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution σz achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented.

  16. Investigation into debris cloud characterizations for oblique hypervelocity impact of projectiles on bumper

    Institute of Scientific and Technical Information of China (English)

    张伟; 管公顺; 庞宝君; 李强; 张永强

    2004-01-01

    All long-duration spacecraft in low-earth-orbit are subject to high velocity impacts by meteoroids and space debris. Such impacts are expected to occur at non-normal incidence angles and can cause severe damage to the spacecraft and its external flight-critical systems and possibly lead to catastrophic failure of the spacecraft.In order to ensure crew safety and proper function of internal and external spacecraft systems, the characteristics of a debris cloud generated by such impacts must be known. An analytical model is therefore developed for the characterization of the penetration and ricochet debris clouds created by the hypervelocity impact of an aluminum spherical projectile on an aluminum plate. This model employs normal and oblique shock wave theory to characterize the penetration and ricochet processes. The prediction results of center-of-mass trajectory and leading velocity of penetration and ricochet debris clouds are obtained and compared with numerical and experimental results in figures.

  17. Numerical simulation of three-dimensional transonic turbulent projectile aerodynamics by TVD schemes

    Science.gov (United States)

    Shiau, Nae-Haur; Hsu, Chen-Chi; Chyu, Wei-Jao

    1989-01-01

    The two-dimensional symmetric TVD scheme proposed by Yee has been extended to and investigated for three-dimensional thin-layer Navier-Stokes simulation of complex aerodynamic problems. An existing three-dimensional Navier-stokes code based on the beam and warming algorithm is modified to provide an option of using the TVD algorithm and the flow problem considered is a transonic turbulent flow past a projectile with sting at ten-degree angle of attack. Numerical experiments conducted for three flow cases, free-stream Mach numbers of 0.91, 0.96 and 1.20 show that the symmetric TVD algorithm can provide surface pressure distribution in excellent agreement with measured data; moreover, the rate of convergence to attain a steady state solution is about two times faster than the original beam and warming algorithm.

  18. Projectile fragmentation at intermediate energies and the production of light neutron rich exotic nuclei

    International Nuclear Information System (INIS)

    The possibility for projectile fragmentation with intermediate energy heavy ions (20< E<90MeV/u) to be a powerful 100l for producing new exotic species is illustrated here. The existing methods using heavy ions are first reviewed briefly. The mechanism responsible for fragment production at the Ganil energies is then described. The main features which are of interest as far as the production of n-rich nuclides is concerned will be emphasized. This will allow some predictions for the production rates of n-rich isotopes. The LISE spectrometer is then described and finally the results of the first experiment using the reaction Ar+Ta at 1,8 GeV where the neutron drip line has been reached for some light nuclei are presented

  19. Nuclear Fragmentation Induced by Relativistic Projectiles Studied in the 4$\\pi$ Configuration of Plastic Track Detectors

    CERN Multimedia

    2002-01-01

    % EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...

  20. Special features of isomeric ratios in nuclear reactions induced by various projectile particles

    Science.gov (United States)

    Danagulyan, A. S.; Hovhannisyan, G. H.; Bakhshiyan, T. M.; Martirosyan, G. V.

    2016-05-01

    Calculations for ( p, n) and (α, p3 n) reactions were performed with the aid of the TALYS-1.4 code. Reactions in which the mass numbers of target and product nuclei were identical were examined in the range of A = 44-124. Excitation functions were obtained for product nuclei in ground and isomeric states, and isomeric ratios were calculated. The calculated data reflect well the dependence of the isomeric ratios on the projectile type. A comparison of the calculated and experimental data reveals, that, for some nuclei in a high-spin state, the calculated data fall greatly short of their experimental counterparts. These discrepancies may be due to the presence of high-spin yrast states and rotational bands in these nuclei. Calculations involving various level-density models included in the TALYS-1.4 code with allowance for the enhancement of collective effects do not remove the discrepancies in the majority of cases.

  1. Projectiles Impact Assessment of Aircraft Wing Structures with Real Dynamic Load

    Science.gov (United States)

    Han, Lu; Han, Qing; Wang, Changlin

    2015-07-01

    This paper presents an analysis to achieve the impact damage of the wing structure under real dynamic load. MPCCI tools are utilized to convert wing aerodynamic load into structural Finite Element Method (FEM) node load. The ANSYS/LS-DYNA code is also used to simulate the dynamic loading effects of the wing structure hit by several projectiles, including both active damage mechanism and common damage mechanism. In addition, structural node force on the leading edge and the midline is compared to the aerodynamic load separately. Furthermore, the statistical analysis of the penetrating size and the stress concentration around the damage holes indicates that under the same load situation, the structural damage efficiency of active damage mechanism is significantly higher than the one of common damage mechanism.

  2. Modeling of Normal Perforation of Reinforced Concrete Slabs by a Rigid Projectile

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiaowei; LI Xiaoli

    2006-01-01

    An analytical model on the normal perforation of reinforced concrete slabs is constructed.The effect of reinforcing bars is further hybridized in a general three-stage model consisting of initial cratering,tunnelling and shear plugging.Besides three dimensionless numbers,i.e.,the impact function /,the geometry function of projectile N and the dimensionless thickness of concrete target χ,which are employed to predict the ballistic performance of perforation of concrete slabs,the reinforcement ratio ρs of concrete and the tensile strength fs of reinforcing bars are considered as the other main factors influencing the perforation process.Simpler solutions of ballistic performances of normal perforation of reinforced concrete slabs are formulated.Theoretical predictions agree well with individual published experimental data.

  3. Experimental Investigation on the Ballistic Resistace of Metal Plates Subjected to Impact of Rigid Projectiles

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; DENG Yun-fei; CAO Zong-sheng

    2012-01-01

    The ballistic performance of monolithic and multi-layered steel plates impacted by ogival-nosed projectiles was investigated by using a gas gun experimentally.The total thickness of in-contact multi-layered target was equally to that of monolithic target.The results show that,for the high strength targets,the monolithic targets have greater ballistic limit velocities than multi-layered targets,and also the ballistic limit velocities of targets decrease with the increase of the number of layers.However,for the low strength targets,the monolithic targets have lower ballistic limit velocities than multi-layered targets.The differences in target capacity between various impact conditions can be related to the transitions of perforation mechanisms and failure models.

  4. Global optical-model potentials for the elastic scattering of sup(6,7)Li projectiles

    International Nuclear Information System (INIS)

    Simultaneous fits have been made to 44 6Li data sets covering the mass range 24-208 and the energy range 13-156 MeV in order to determine an average ('global') optical-model potential for 6Li scattering. A similar study has been made for 25 7Li data sets over the same mass range and an energy range of 28-88 MeV to find an average 7Li potential. With Saxon-Woods factors, constant values may be used for all parameters except for the depth of the imaginary potential which decreases in magnitude with increasing mass. The necessity of energy dependence, Coulomb correction and (for 7Li) a symmetry term is investigated. The variation of the integral properties of the potentials is discussed, and also a comparison is made for the two projectiles. Application of the global potentials is made to inelastic scattering and single-nucleon transfer reactions. (orig.)

  5. Determination of absolute transition probabilities in 128Xe via projectile Coulomb excitation

    International Nuclear Information System (INIS)

    Recently, lifetimes of low-lying excited states in 128Xe were measured using the plunger technique after projectile Coulomb excitation. This experiment was performed at the JYFL, Jyvaeskylae using the JUROGAM Ge-detector array and the Cologne coincidence plunger device equipped with an array of 32 small Si-detectors. The Si-detectors were used to measure the reaction kinematics by registering target-like nuclei scattered in forward direction. In order to cross-check the results obtained from the recoil distance Doppler shift analysis an evaluation of the measured excitation cross-sections was performed with the computer code GOSIA. In addition deorientation effects were investigated and effort was made to extract absolute quadrupole moments. Details of the experiment and the calculations are presented.

  6. Projectile X-ray emission in relativistic ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Shadi Mohammad Ibrahim

    2010-03-16

    This work reports on the study of the projectile X-ray emission in relativistic ion-atom collisions. Excitation of K-shell in He-like uranium ions, electron capture into H-like uranium ions and Simultaneous ionization and excitation of initially He-like uranium ions have been studied using the experimental storage ring at GSI. For the K{sub {alpha}}{sub 1} and K{sub {alpha}}{sub 2} transitions originating from the excitation of the He-like uranium ions, no alignment was observed. In contrast, the Ly{sub {alpha}}{sub 1} radiation from the simultaneous ionization-excitation process of the He-like uranium ions shows a clear alignment. The experimental value leads to the inclusion of a magnetic term in the interaction potential. The capture process of target electrons into the highly-charged heavy ions was studied using H-like uranium ions at an incident energy of 220 MeV/u, impinging on N{sub 2} gas-target. It was shown that, the strongly aligned electrons captured in 2p{sub 3/2} level couple with the available 1s{sub 1/2} electron which shows no initial directional preference. The magnetic sub-state population of the 2p{sub 3/2} electron is redistributed according to the coupling rules to the magnetic sub-states of the relevant two-electron states. This leads to the large anisotropy in the corresponding individual ground state transitions contributing to the K{sub {alpha}}{sub 1} emission. From the K{sub {alpha}}{sub 1}/K{sub {alpha}}{sub 2} ratio, the current results show that the incoherent addition of the E1 and M2 transition components yield to an almost isotropic emission of the total K{sub {alpha}}{sub 1}. In contrast to the radiative electron capture, the experimental results for the K-shell single excitation of He-like uranium ions indicate that only the {sup 1}P{sub 1} level contributes to the K{sub {alpha}}{sub 1} transition. For this case, the anisotropy parameter {beta}{sub 20} was found to be -0.20{+-}0.03. This work also reports on the study of a two

  7. Relativistic exotic nuclei as projectile beams. New perspectives of studies on the properties of nuclei

    International Nuclear Information System (INIS)

    Examinations of the production cross-sections and the kinematics permitted refinement of model concepts of the peripheral reactions in exotic nuclei at energies from 100 to 1000 A MeV. Due to the strong selectivity and resolution achieved it was possible to discover a large number of novel isotopes at the fragment separator FRS, despite the relatively low projectile beam intensities of the SIS. The two twice magic nuclei found, Ni 78 and Sn 100, are particularly interesting, as they could not be measured so far with other experimental systems. Fission of relativistic uranium ions proved to be a particularly successful process yielding many medium-heavy, neutron-rich nuclei. Insight into the structure of light neutron halos could be improved. The superlarge spatial dimensions of the nuclear halos is discussed. (orig./CB)

  8. A Monolithic High-G SOI-MEMS Accelerometer for Measuring Projectile Launch and Flight Accelerations

    Directory of Open Access Journals (Sweden)

    Bradford S. Davis

    2006-01-01

    Full Text Available Analog Devices (ADI has designed and fabricated a monolithic high-g acceleration sensor (ADXSTC3-HG fabricated with the ADI silicon-on-insulator micro-electro-mechanical system (SOI-MEMS process. The SOI-MEMS sensor structure has a thickness of 10 um, allowing for the design of inertial sensors with excellent cross-axis rejection. The high-g accelerometer discussed in this paper was designed to measure in-plane acceleration to 10,000 g while subjected to 100,000 g in the orthogonal axes. These requirements were intended to meet Army munition applications. The monolithic sensor was packaged in an 8-pin leadless chip carrier (LCC-8 and was successfully demonstrated by the US Army Research Laboratory (ARL as part of an inertial measurement unit during an instrumented flight experiment of artillery projectiles launched at 15,000 g.

  9. Damage visualization and deformation measurement in glass laminates during projectile penetration

    Directory of Open Access Journals (Sweden)

    Elmar Strassburger

    2014-06-01

    Full Text Available Transparent armor consists of glass-polymer laminates in most cases. The formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such laminates. In order to clarify the course of events during projectile penetration, an experimental technique was developed, which allows visualizing the onset and propagation of damage in each single layer of the laminate. A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of 1 MHz in a backlit photography set-up. With this technique, the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm × 500 mm. Damage evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 11.1 g in the impact velocity range from 800 to 880 m/s. In order to measure the deformation of single glass plates within the laminates, a piece of reflecting tape was attached to the corresponding glass plate, and photonic Doppler velocimetry (PDV was applied. With the photonic Doppler velocimeter, an infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the detector. The simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of fracture. The analysis of the experimental data was supported by numerical simulations, using the AUTODYN commercial hydro-code.

  10. Radiolysis of astrophysical ice analogs by energetic ions: the effect of projectile mass and ice temperature.

    Science.gov (United States)

    Pilling, Sergio; Duarte, Eduardo Seperuelo; Domaracka, Alicja; Rothard, Hermann; Boduch, Philippe; da Silveira, Enio F

    2011-09-21

    An experimental study of the interaction of highly charged, energetic ions (52 MeV (58)Ni(13+) and 15.7 MeV (16)O(5+)) with mixed H(2)O : C(18)O(2) astrophysical ice analogs at two different temperatures is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by cosmic rays inside dense, cold astrophysical environments, such as molecular clouds or protostellar clouds as well at the surface of outer solar system bodies. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a CsI substrate at 13 K and 80 K. In situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross section at 13 K of both H(2)O and CO(2) is about 3-4 times smaller when O ions are employed. The ice temperature seems to affect differently each species when the same projectile was employed. The formation cross section at 13 K of molecules such as C(18)O, CO (with oxygen from water), and H(2)O(2) increases when Ni ions are employed. The formation of organic compounds seems to be enhanced by the oxygen projectiles and at lower temperatures. In addition, because the organic production at 13 K is at least 4 times higher than the value at 80 K, we also expect that interstellar ices are more organic-rich than the surfaces of outer solar system bodies.

  11. Damage visualization and deformation measurement in glass laminates during projectile penetration

    Institute of Scientific and Technical Information of China (English)

    Elmar STRASSBURGER; Steffen BAUER; Gregor POPKO

    2014-01-01

    Transparent armor consists of glass-polymer laminates in most cases. The formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such laminates. In order to clarify the course of events during projectile penetration, an experimental technique was developed, which allows visualizing the onset and propagation of damage in each single layer of the laminate. A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of 1 MHz in a backlit photography set-up. With this technique, the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm ? 500 mm. Damage evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 11.1 g in the impact velocity range from 800 to 880 m/s. In order to measure the deformation of single glass plates within the laminates, a piece of reflecting tape was attached to the corresponding glass plate, and photonic Doppler velocimetry (PDV) was applied. With the photonic Doppler velocimeter, an infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the detector. The simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of fracture. The analysis of the experimental data was supported by numerical simulations, using the AUTODYN commercial hydro-code.

  12. Vector projectile imaging: time-resolved dynamic visualization of complex flow patterns.

    Science.gov (United States)

    Yiu, Billy Y S; Lai, Simon S M; Yu, Alfred C H

    2014-09-01

    Achieving non-invasive, accurate and time-resolved imaging of vascular flow with spatiotemporal fluctuations is well acknowledged to be an ongoing challenge. In this article, we present a new ultrasound-based framework called vector projectile imaging (VPI) that can dynamically render complex flow patterns over an imaging view at millisecond time resolution. VPI is founded on three principles: (i) high-frame-rate broad-view data acquisition (based on steered plane wave firings); (ii) flow vector estimation derived from multi-angle Doppler analysis (coupled with data regularization and least-squares fitting); (iii) dynamic visualization of color-encoded vector projectiles (with flow speckles displayed as adjunct). Calibration results indicated that by using three transmit angles and three receive angles (-10°, 0°, +10° for both), VPI can consistently compute flow vectors in a multi-vessel phantom with three tubes positioned at different depths (1.5, 4, 6 cm), oriented at different angles (-10°, 0°, +10°) and of different sizes (dilated diameter: 2.2, 4.4 and 6.3 mm; steady flow rate: 2.5 mL/s). The practical merit of VPI was further illustrated through an anthropomorphic flow phantom investigation that considered both healthy and stenosed carotid bifurcation geometries. For the healthy bifurcation with 1.2-Hz carotid flow pulses, VPI was able to render multi-directional and spatiotemporally varying flow patterns (using a nominal frame rate of 416 fps or 2.4-ms time resolution). In the case of stenosed bifurcations (50% eccentric narrowing), VPI enabled dynamic visualization of flow jet and recirculation zones. These findings suggest that VPI holds promise as a new tool for complex flow analysis.

  13. Role of projectile breakup effects and intrinsic degrees of freedom on fusion dynamics

    Science.gov (United States)

    Singh Gautam, Manjeet

    2016-05-01

    This article analyzes the fusion dynamics of loosely bound and stable projectiles with Zr-target isotopes within the context of the coupled channel approach and the energy-dependent Woods-Saxon potential model (EDWSP model). In the case of the 28Si + 90Zr reaction, the coupling to the inelastic surface excitations results in an adequate description of the observed fusion dynamics while in case of the 28Si + 94Zr reaction, the coupling to collective surface vibrational states as well as the neutron (multi-neutron) transfer channel is necessary in the coupled channel calculations to reproduce the below-barrier fusion data. However, the EDWSP model calculation provides an accurate explanation of the fusion data of 28Si + 90,94Zr reactions in the domain of the Coulomb barrier. In the fusion of the 6Li + 90Zr reaction, the inclusion of the nuclear structure degrees of freedom recovers the observed sub-barrier fusion enhancement but results in suppression of the above barrier fusion data by 34% with respect to the coupled channel calculations. Using EDWSP model calculations, this suppression factor is reduced by 14% and consequently, the above-barrier fusion data of 6Li + 90Zr reaction is suppressed by 20% with reference to the EDWSP model calculations. Such fusion suppression at above-barrier energies can be correlated with the breakup of the projectile (6Li) before reaching the fusion barrier, as a consequence of low binding energy. Supported by Dr. D. S. Kothari Post-Doctoral Fellowship Scheme sponsored by University Grants Commission (UGC), New Delhi, India

  14. Radiolysis of astrophysical ice analogs by energetic ions: the effect of projectile mass and ice temperature.

    Science.gov (United States)

    Pilling, Sergio; Duarte, Eduardo Seperuelo; Domaracka, Alicja; Rothard, Hermann; Boduch, Philippe; da Silveira, Enio F

    2011-09-21

    An experimental study of the interaction of highly charged, energetic ions (52 MeV (58)Ni(13+) and 15.7 MeV (16)O(5+)) with mixed H(2)O : C(18)O(2) astrophysical ice analogs at two different temperatures is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by cosmic rays inside dense, cold astrophysical environments, such as molecular clouds or protostellar clouds as well at the surface of outer solar system bodies. The measurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a CsI substrate at 13 K and 80 K. In situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross section at 13 K of both H(2)O and CO(2) is about 3-4 times smaller when O ions are employed. The ice temperature seems to affect differently each species when the same projectile was employed. The formation cross section at 13 K of molecules such as C(18)O, CO (with oxygen from water), and H(2)O(2) increases when Ni ions are employed. The formation of organic compounds seems to be enhanced by the oxygen projectiles and at lower temperatures. In addition, because the organic production at 13 K is at least 4 times higher than the value at 80 K, we also expect that interstellar ices are more organic-rich than the surfaces of outer solar system bodies. PMID:21647477

  15. Korekcija putanje žiroskopski stabilisanog projektila primenom proporcionalne navigacije / Trajectory correction of gyroscopic stabilized projectile using proportional navigation

    Directory of Open Access Journals (Sweden)

    Danilo V. Ćuk

    2010-01-01

    Full Text Available U radu su prikazane metode korekcije putanje žiroskopski stabilisanih projektila primenom proporcionalne navigacije. Sekcija upravljanja tipa 'patka' ugrađena je na klasični projektil radi generisanja aerodinamičke sile. Efikasnost projektila sa korekcijom putanje prikazana je pomoću rezultata numeričke simulacije leta, primenom proporcionalne navigacije sa i bez kompenzacije poremećaja zbog gravitacionog i tangentnog ubrzanja. Analizirani su, takođe, uticaji početnog ugla elevacije i odstupanja ravni upravljanja od ravni praćenja cilja na promašaj projektila. Pokazano je da se precesioni oblik oscilovanja ugaonog kretanja projektila prenosi na ugaonu brzinu linije viziranja cilja koju treba filtrirati kako bi se otklonila pojava rezonantne nestabilnosti leta projektila. / This paper presents the methods of the trajectory correction of gyroscopic stabilized projectiles using different modifications of proportional navigation. The canard section is built into the conventional projectile to generate aerodynamic force. The effectiveness of the trajectory correctable projectile is shown by the results of a flight numerical simulation using proportional navigation with and without the compensation of the disturbance due to gravitational and tangent acceleration. The paper also analyzes the effects of the initial elevation angle and the deflection of the control plane from the target tracking one on the miss distance. It is shown that the precessional mode of the projectile angular motion is transferred to the line of sight rate which should be filtered to prevent the phenomenon of resonance instability of the projectile flight.

  16. Test

    DEFF Research Database (Denmark)

    Bendixen, Carsten

    2014-01-01

    Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers.......Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers....

  17. Ejecta velocity distribution of impact craters formed on quartz sand: Effect of projectile density on crater scaling law

    Science.gov (United States)

    Tsujido, Sayaka; Arakawa, Masahiko; Suzuki, Ayako I.; Yasui, Minami

    2015-12-01

    In order to clarify the effects of projectile density on ejecta velocity distributions for a granular target, impact cratering experiments on a quartz sand target were conducted by using eight types of projectiles with different densities ranging from 11 g cm-3 to 1.1 g cm-3, which were launched at about 200 m s-1 from a vertical gas gun at Kobe University. The scaling law of crater size, the ejection angle of ejecta grains, and the angle of the ejecta curtain were also investigated. The ejecta velocity distribution obtained from each projectile was well described by the π-scaling theory of v0/√{gR} =k2(x0/R)-1/μ, where v0, g, R and x0 are the ejection velocity, gravitational acceleration, crater radius and ejection position, respectively, and k2 and μ are constants mostly depending on target material properties (Housen, K.R., Holsapple, K.A. [2011]. Icarus 211, 856-875). The value of k2 was found to be almost constant at 0.7 for all projectiles except for the nylon projectile, while μ increased with the projectile density, from 0.43 for the low-density projectile to 0.6-0.7 for the high-density projectile. On the other hand, the π-scaling theory for crater size gave a μ value of 0.57, which was close to the average of the μ values obtained from ejecta velocity distributions. The ejection angle, θ, of each grain decreased slightly with distance, from higher than 45° near the impact point to 30-40° at 0.6 R. The ejecta curtain angle is controlled by the two elementary processes of ejecta velocity distribution and ejection angle; it gradually increased from 52° to 63° with the increase of the projectile density. The comparison of our experimental results with the theoretical model of the crater excavation flow known as the Z-model revealed that the relationship between μ and θ obtained by our experiments could not be described by the Z-model (Maxwell, D.E. [1977]. In: Roddy, D.J., Pepin, R.O., Merrill, R.B. (Eds.), Impact and Explosion Cratering

  18. 考虑刚性弹弹头形状的混凝土(岩石)靶体侵彻深度半理论分析%Semi-theoretical analyses for penetration depth of rigid projectiles with different nose geometries into concrete (rock) targets

    Institute of Scientific and Technical Information of China (English)

    吴昊; 方秦; 龚自明

    2012-01-01

    Based on the dynamic spherical cavity-expansion theory and the two-stage penetration model consisting of cratering and tunneling, a dimensionless formula was proposed for normal penetration depth of rigid projectiles into concrete and rock targets by taking a truncated-ogive nose projectile as an example. In the proposed formula, the surface integration method was applied, and the mass ratio and the impact factor were introduced, as well as the dimensionless coefficients denoting the projectile nose geometry and the projectile-target friction effect, to consider the variation of projectile nose geometry, cratering depth, and tangential resistance on projectiles. And the proposed formula can be regressed to the classic penetration formulae in special cases. The proposed formula was validated by comparing the penetration depths predicted by the proposed formula with those predicted by the existing ten classic empirical and semi-empirical formulae as well as the experimental data from eight field shot tests of concrete and rock targets hit by projectiles with different nose geometries. Based on the tests and parametric analyses, the corresponding parameter values were recommended aiming to different nose projectiles, including the dynamic projectile-target frictional coefficient of concrete and rock targets, as well as the linear coefficient of cratering depth related to the impact factor.%基于动力球型空腔膨胀理论和“冲击成坑+钻孔区”两阶段侵彻模型,以截卵形弹头弹体为例,运用曲面积分,引入表征弹头形状和弹靶摩擦效应的量纲—系数、质量比和冲击因子,提出了综合考虑弹头形状变化、成坑区深度、弹靶摩擦阻力的混凝土和岩石靶体的刚性弹垂直侵彻深度的计算公式.该公式在相关参数取特殊值时,可退化为经典的侵彻深度计算公式.通过与8组不同弹头形状弹体冲击混凝土和岩石靶体的侵彻实验数据、已有10个(半)经验公式

  19. 平抛运动演示仪的改进%Improvement of horizontal projectile device

    Institute of Scientific and Technical Information of China (English)

    李燕秋; 代伟; 罗微; 马兰; 黄军

    2015-01-01

    Some improvements were introduced to overcome the shortages of the experiment de‐vice of demonstrating horizontal projectile motion in teaching materials .In horizontal direction ,an e‐lectromagnet was used to make two balls move at the same time .After passing through glass tubes with same bending ,one ball was horizontally projected ,the other was in uniform motion .Finally , two balls would collide with each other .This showed that horizontal projection of horizontal projectile motion is uniform motion .In vertical direction ,a time‐delay circuit was designed using single chip mi‐croprocessor .When the horizontally projected ball and the free‐falling ball landed ,LEDs would emit red light and green light ,respectively ,enabled one to judge if the two balls fell to the ground simulta‐neously ,namely one could judge if a horizontally projected object moves like a free‐falling body in the vertical direction .%针对高中物理教科版教材中平抛运动的演示实验装置存在的不足,对平抛运动演示仪进行了改进。该演示仪在水平方向上,利用电磁铁控制2个小球开始运动时间,当小球通过弯度相同的2个玻璃管后,一个做平抛运动,一个做匀速直线运动,最后会相碰,由此说明平抛运动的在水平方向上是匀速直线运动。在竖直方向上,利用单片机自制了延时电路,当做平抛运动的小球和做自由落体运动的小球落地时,发光二极管会分别发出红光和绿光,通过2个二极管的发光情况可以判断出两小球同时落地,即可以判断出平抛运动的竖直方向上是自由落体运动。

  20. Numerical Study on Anti-Penetration Process of Alumina Ceramic (AD95) to Tungsten Long Rod Projectiles

    Science.gov (United States)

    Zhang, Xianfeng; Zhang, Niansong; Li, Yongchi

    Numerical studies were conducted on the ballistic performance of alumina ceramic (AD95) tiles based on depth of penetration method, when subjected to normal impact of tungsten long rod projectiles at velocities ranging from 1100 to 2000 ms-1. The residual depth on after-effect target was derived in each case, and the ballistic efficiency factor was determined using the corresponding penetration depth on medium carbon steel. Anti-penetration experiment study of the AD95 ceramic tiles to tungsten long rod projectiles has been carried out to verify the accuracy of numerical simulation model. The result shows that numerical simulation results agree well with the corresponding experiment results and AD95 ceramic has excellent ballistic performance than medium carbon steel. The ballistic efficiency factor increases with velocity increasing when impact velocity lower than 1300 ms-1, and when it was higher than 1300 ms-1 the ballistic efficiency factor has almost no difference.

  1. Dispersion sensitivity of the eight inch advanced ramjet munitions technology projectile due to wind and minor thrust errors

    Science.gov (United States)

    Poole, S. R.

    1984-09-01

    Advanced Ramjet Munitions Technology (ARMT) is an ongoing DARPA project to research ramjet munitions. The ARMT eight inch projectile uses ramjet thrust for a boosted trajectory, but operates on a thrust drag balance concept to create pseudovacuum trajectory during powered flight. The trajectory was analyzed using an IBM-370 computer simulation for three and five degrees of freedom. Work was also done to adapt the Ballistics Research Laboratories six degrees of freedom program to the IBM system. Projectile aerodynamic and mass properties were obtained from the Norden Systems Wind Tunnel Data. Dispersion from the vaccuum trajectory due to wind prior to ramjet burnout proved minor. Dispersion due to constant thrust errors under 5% was within a 600 radius at terminal guidance over a range of 33 miles.

  2. Effects of projectile resonances on the total, Coulomb, and nuclear breakup cross sections in the 6Li+152Sm reaction

    Science.gov (United States)

    Mukeru, B.; Lekala, M. L.

    2016-08-01

    In this paper we analyze the effects of the projectile resonances on the total, Coulomb, and nuclear breakup cross sections as well as on the Coulomb-nuclear interferences at different arbitrary incident energies. It is found that these resonances have non-negligible effects on the total, Coulomb, and nuclear breakup cross sections. Qualitatively, they have no effects on the constructiveness or destructiveness of the Coulomb-nuclear interferences. Quantitatively, we obtained that these resonances increase by 7.38%, 7.58%, and 20.30% the integrated total, Coulomb, and nuclear breakup cross sections, respectively at Elab=35 MeV . This shows that the nuclear breakup cross sections are more affected by the effects of the projectile resonances than their total and Coulomb breakup counterparts. We also obtain that the effects of the resonances on the total, Coulomb, and nuclear breakup cross sections decrease as the incident energy increases.

  3. Impact cratering experiments into quartzite, sandstone and tuff: The effects of projectile size and target properties on spallation

    Science.gov (United States)

    Poelchau, Michael H.; Kenkmann, Thomas; Hoerth, Tobias; Schäfer, Frank; Rudolf, Michael; Thoma, Klaus

    2014-11-01

    Impact cratering experiments were performed on quartzite, tuff, and dry and water-saturated sandstones in the framework of the MEMIN research unit. 2.5-12 mm diameter projectiles were accelerated to ∼5 km/s. Evaluation of the resulting craters shows that crater volumes and crater efficiencies of large-scale experiments are greater than predicted by strength scaling laws. A method to approximate the transient crater volume shows that this effect is largely due to an increase in spallation. Strength scaling laws are used to determine the reduction of tensile strength in large-scale experiments and show a decrease by a factor of 1.8-3.6. This strength reduction can be correlated with a decrease in strain rate for larger projectiles, and with the Weibull theory of strength reduction for larger rock sample sizes. Further variations in spallation are observed between different target materials; a decrease in spall is suggested to be controlled by increased porosity.

  4. FISH analysis of the integra-tion patterns in transgenicrice co-transformed by micro-projectile bombardment

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using multi-color fluorescence in situ hybridization (FISH), we localized transferred barnase-ps1 and pHctinG DNA sequences onto chromosomes of two transgenic rice plants, named Q12 and Q13, both of which were produced by micro-projectile bombardment. In both Q12 and Q13, each detected cell showed 2-3 signal spots on their chromosomes respectively. The signals of both barnase-ps1 and pHctinG were mostly detected in the adjacent chromosomal sites in which their signals were overlapped and could be recognized by the signal color on the metaphase chromosomes. Fiber FISH further demonstrated that the multiple copies in each of the two DNA sequences distributed adjacently on the DNA fiber in Q13. Combined with the results of Southern hybridization, the possible integration patterns in transgenic rice co-transformed by micro-projectile bombardment have been discussed.

  5. Charge correlations in the breakup of gold projectiles in reactions at E/A=600 MeV

    International Nuclear Information System (INIS)

    In the present thesis the charge correlations in the breakup of gold projectiles in heavy ion collisions at an incident energy of E/A=600 MeV were studied. Thereby it has been proved that the sum of the charges from the projectile source under exclusion of the protons (Zbound) is saliently suited for the classification of the nuclear reactions. At large values of Zbound we fins fission and spallation reactions. For smaller values of Zbound we observe events with an increasing number of medium-heavy fragments. Thereby the multifragment events appear in the Dalitz diagrams as a continuation of more symmetric becoming spallation events. In reactions with Zbound ≅ 35 the conditions for the formation of medium-heavy fragments are optimal and the multifragment events represent the dominating exit channel. A mean multiplicity of the medium-heavy fragments of ≅ 4 is reached. (orig./HSI)

  6. Study of events in absence of target/projectile fragments in interactions of nuclei with emulsion at 4.5 and 4.1 AGeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, Magda A., E-mail: dr.magda2006@hotmail.co [Physics Department, Faculty of Science, Sana' s University (Yemen); Fakhraddin, S., E-mail: sakinafa1@hotmail.co [Physics Department, Faculty of Science, Sana' s University (Yemen)

    2009-12-01

    This work is devoted to study two types of events. Type (a): events with no target fragments, the incident nucleus is dissociated in emulsion accompanied with the pions. Type (b): events with no projectile fragments, total break-up of the two colliding nuclei into relatively small fragments. Case of central collisions. The main characteristics of these reactions, that is multiplicity distributions of projectile and target fragments have been studied and compared for interactions of {sup 4}He, {sup 12}C, {sup 16}O, {sup 22}Ne and {sup 28}Si nuclei with emulsion at almost same momentum. The dependence of the mean multiplicity of different PFs on the projectile mass is investigated. Also the percentage of occurrence of these two events for different projectiles are analyzed.

  7. Devices for launching 0. 1-g projectiles to 150 km/s or more to initiate fusion. Part 2. Railgun accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Hawke, R.S.

    1979-07-06

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is studied. The analysis revealed that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, single- and multistage accelerators were designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities.

  8. Devices for launching 0.1-g projectiles to 150 km/s or more to initiate fusion. Part 2. Railgun accelerators

    International Nuclear Information System (INIS)

    The possibility of using a railgun accelerator to launch 0.1-g projectiles to hypervelocities (150 km/s or more) to initiate thermonuclear fusion is studied. The analysis revealed that a railgun with a plasma-arc armature is a viable approach to the goal. When calculating the railgun's probable performance, it was discovered that this launch system might possibly be designed to avoid adverse effects from boundary layer drag. An appendix provided by A.C. Buckingham summarizes his calculations that predict the amount of erosive drag between projectile and rail. Finally, it was found that certain properties of railgun and projectile materials can impose operational limits. Using these limits, single- and multistage accelerators were designed. Within such limits, a railgun could accelerate a 0.1-g projectile to hypervelocities

  9. Comparison of high speed movie and flash x-ray measurement of the translational and rotational motions of projectiles penetrating gelatin

    International Nuclear Information System (INIS)

    Projectiles penetrating a gelatin block were simultaneously measured by a high speed movie camera, Dynafax, and by a sequential, orthogonal, flash x-ray system. The eight orthogonal views of the x-ray system provided position and orientation of the projectiles vs. time. From onset of tumble in the gelatin, owing to gyroscopic instability, the growth of yaw was the same for each round in a replicated set. This phenomenon provided a legitimate procedure for pooling the x-ray data, giving well determined curves of velocity decay and yaw growth. The movie camera observed the progress of the cavity formed by the projectile. The resulting velocity decay of the cavity tip was compared to that of the projectile as measured by the x-ray technique. (author)

  10. Helium projectile fragment emission in interactions of 197Au with emulsion at 10.7A GeV

    International Nuclear Information System (INIS)

    The total and partial production cross-sections of the multiple helium fragments emitted in 10.7A GeV 197Au–emulsion interactions are reported and compared with those obtained from different projectiles at high energies. The multiplicity distributions of the helium fragments exhibit a KNO scaling. The dependence of Cq moments and on the mass number of the incident beams is plotted. (author)

  11. Role of projectile breakup in {sup 6}He and {sup 6}Li induced fusion reactions around barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Anju; Kharab, Rajesh, E-mail: kharabrajesh@rediffmail.com

    2015-09-15

    The influence of projectile breakup on fusion cross section for {sup 6}He + {sup 209}Bi, {sup 6}He + {sup 64}Zn, {sup 6}Li + {sup 209}Bi and {sup 6}Li + {sup 64}Zn reactions at near barrier energies is studied within the framework of quantum diffusion approach. The breakup does not affect the fusion induced by {sup 6}He, whereas a significant suppression for {sup 6}Li induced reaction is observed in below barrier energy region.

  12. Interior Ballistics Two-Phase Reactive Flow Model Applied to Large Caliber Guided Projectile-Gun System

    OpenAIRE

    Mahmoud Rashad; XiaoBing Zhang; Hazem El Sadek

    2014-01-01

    Transient complex phenomena take place in a gun during interior ballistic cycle. Understanding these phenomena clearly and describing the mathematical models accurately are crucial to predict the behavior of gun system considering firing safety and performance. A mathematical model based on Eulerian-Eulerian approach for reactive gas-solid flow arising during interior ballistic cycle inside large caliber naval gun guided projectile system was developed. The model included the governing equati...

  13. Enhanced excitation of Giant Pairing Vibrations in heavy-ion reactions induced by weakly-bound projectiles

    CERN Document Server

    Fortunato, L; Sofia, H M; Vitturi, A

    2002-01-01

    The use of radioactive ion beams is shown to offer the possibility to study collective pairing states at high excitation energy, which are not usually accessible with stable projectiles because of large energy mismatch. In the case of two-neutron stripping reactions induced by 6He, we predict a population of the Giant Pairing Vibration in 208Pb or 116Sn with cross sections of the order of a millibarn, dominating over the mismatched transition to the ground state.

  14. Large-scale 3D modeling of projectile impact damage in brittle plates

    Science.gov (United States)

    Seagraves, A.; Radovitzky, R.

    2015-10-01

    The damage and failure of brittle plates subjected to projectile impact is investigated through large-scale three-dimensional simulation using the DG/CZM approach introduced by Radovitzky et al. [Comput. Methods Appl. Mech. Eng. 2011; 200(1-4), 326-344]. Two standard experimental setups are considered: first, we simulate edge-on impact experiments on Al2O3 tiles by Strassburger and Senf [Technical Report ARL-CR-214, Army Research Laboratory, 1995]. Qualitative and quantitative validation of the simulation results is pursued by direct comparison of simulations with experiments at different loading rates and good agreement is obtained. In the second example considered, we investigate the fracture patterns in normal impact of spheres on thin, unconfined ceramic plates over a wide range of loading rates. For both the edge-on and normal impact configurations, the full field description provided by the simulations is used to interpret the mechanisms underlying the crack propagation patterns and their strong dependence on loading rate.

  15. Sensitivity of N/Z ratio in projectile break-up of isobaric systems

    Directory of Open Access Journals (Sweden)

    De Filippo E.

    2016-01-01

    Full Text Available The binary break-up of projectile-like fragments in non central heavy-ion collisions follows different decay patterns, from equilibrated emission towards dynamical (prompt fission. Recently, comparing two systems with different N/Z in the entrance channel, it has been shown that the dynamical emission cross-section is enhanced for the most neutron rich system while the statistical emission cross-section is independent from the isotopic composition. In order to understand this dependence and disentangle it from the initial size of the nuclei, we have studied the two isobaric systems 124Xe+64 Zn and 124Xe+64 Ni at 35 A MeV (InKiIsSy experiment, in comparison with the previous studied reactions (124Sn +64 Ni and 112Sn +58 Ni at the same bombarding energy. We present the first results evidencing a striking similar effect in the dynamical decay as a function of the N/Z of the target for equal size systems.

  16. Failure mechanism of monolayer graphene under hypervelocity impact of spherical projectile.

    Science.gov (United States)

    Xia, Kang; Zhan, Haifei; Hu, De'an; Gu, Yuantong

    2016-01-01

    The excellent mechanical properties of graphene have enabled it as appealing candidate in the field of impact protection or protective shield. By considering a monolayer graphene membrane, in this work, we assessed its deformation mechanisms under hypervelocity impact (from 2 to 6 km/s), based on a serial of in silico studies. It is found that the cracks are formed preferentially in the zigzag directions which are consistent with that observed from tensile deformation. Specifically, the boundary condition is found to exert an obvious influence on the stress distribution and transmission during the impact process, which eventually influences the penetration energy and crack growth. For similar sample size, the circular shape graphene possesses the best impact resistance, followed by hexagonal graphene membrane. Moreover, it is found the failure shape of graphene membrane has a strong relationship with the initial kinetic energy of the projectile. The higher kinetic energy, the more number the cracks. This study provides a fundamental understanding of the deformation mechanisms of monolayer graphene under impact, which is crucial in order to facilitate their emerging future applications for impact protection, such as protective shield from orbital debris for spacecraft. PMID:27618989

  17. Simulation and Experiment of Projectile Penetrate into Steel Target Acceleration Signal Processing

    Directory of Open Access Journals (Sweden)

    Wen Feng

    2011-03-01

    Full Text Available For a comprehensive and objective understanding of the dynamic overload character of projectile penetrate into a steel target, using the simulating software ANSYS/LS-DYNA, adopting of the corresponding ammunition and target model, and the process of the ammunition penetrate the steel target was simulated and computed, the stress distribution map, mode and some results were got, using ball cartridge experiment, the original overload curves and high speed camera results were got. In this paper, the acceleration signals, which are obtained by the embedded high-overload electronic solid recorder at the experiment of armor-piercing bullet penetrating steel target, was done of wave filtering and integral analysis and so on in time domain, power spectrum was got through FFT in frequency-domain, as well as Wigner-Ville analysis and wavelet analysis in timefrequency. The characteristic signal when armor-piercing bullet penetrates steel target under certain conditions was obtained. Through signal processing and comprehensive analysis, a kind of signal processing method was provided to engineers, by which concerned parameters can be got.

  18. Protection of Cities from Small Rockets, Missiles, Projectiles and Mortar Shells

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The authors suggest a low cost closed AB-Dome, which may protect small cities such as Sederot from rockets, mortar shells, chemical and biological weapons. The offered AB-Dome is also very useful in peacetime because it protects the city from outside weather (violent storms, hail) and creates a fine climate within the Dome. The roughly hemispherical AB-Dome is a gigantic inflated thin transparent film, located at altitude up to 1 - 5 kilometers, which converts the city into a closed-loop air system. The film may be armored with a basalt or steel grille or cloth pocket-retained stones that destroy (by collision or detonation) incoming rockets, shells and other projectiles. Such an AB-Dome would even protect the city in case of a third-party nuclear war involving temporary poisoning of the Earth atmosphere by radioactive dust. The building of the offered dome is easy; the film spreads on the ground, the fan engines turn on and the cover rises to the needed altitude and is supported there by a small internal ove...

  19. Parameterization of fusion barriers for light-projectiles-induced reactions using the proximity approach

    Science.gov (United States)

    Gharaei, R.; Sheibani, J.

    2016-05-01

    In this article we propose a pocket formula for fusion barriers calculated by three versions of the proximity formalism, namely AW 95, Bass 80 and Prox. 2010 potentials, for fusion reactions involving the collisions of the proton and helium projectiles with different targets in mass ranges 51≤ AT ≤ 130 and 40≤ AT ≤ 233 , respectively. For the first type of the colliding systems, it is shown that the proposed pocket formulas are able to predict the actual values of RB and VB within accuracies of ±0.4% and ±0.45% , respectively. Moreover, for the second type of the selected reactions, these accuracies are obtained ±0.24% and ±0.36% , respectively. In this study, the ability of the present pocket formulas is also demonstrated to predict the exact values of the fusion cross sections for our selected mass ranges. A comparison with the results of the previous pocket formulas reveals that our parameterized forms are more successful to reproduce the empirical data of the barrier height and position in the proton- and helium-induced reactions.

  20. Interplay of projectile breakup and target excitation in reactions induced by weakly-bound nuclei

    CERN Document Server

    Gomez-Ramos, M

    2016-01-01

    In this work, we reexamine the extension of the CDCC formalism to include target excitation and apply it to a variety of reactions to study the effect of breakup on inelastic cross sections. We use a transformed oscillator basis to discretize the continuum of the projectiles in the different reactions and use the extended CDCC method developed in this work to solve the resulting coupled differential equations. A new code has been developed to perform the calculations. Reactions 58Ni(d, d) 58Ni*, 24Mg(d, d) 24Mg* , 144Sm( 6Li, 6Li) 144Sm* and 9Be( 6Li, 6Li) 9Be* are studied. Satisfactory agreement is found between experimental data and extended CDCC calculations. The studied CDCC method is proved to be an accurate tool to describe target excitation in reactions with weakly-bound nuclei. Moderate effects of breakup on inelastic observables are found for the reactions studied. Cross section magnitudes are not modified much, but angular distributions present smoothing when opposed to calculations without breakup.

  1. Proof-of-concept development of PXAMS (projectile x-ray accelerator mass spectrometry)

    Energy Technology Data Exchange (ETDEWEB)

    Proctor, I.D.; Roberts, M.L.; McAninch, J.E.; Bench, G.S.

    1996-03-01

    Prior to the current work, accelerator mass spectrometry (AMS) was limited to a set of {approximately}8--10 isotopes. This limitation is caused primarily by the inability to discriminate against stable atomic isobars. An analysis scheme that combines the isotopic sensitivity of AMS with similar isobar selectivity would open a large new class of isotope applications. This project was undertaken to explore the use of characteristic x rays as a method for the detection and identification of ions,and to allow the post-spectrometer rejection of isobaric interferences for isotopes previously inaccessible to AMS. During the second half of FY94 (with Advanced Concepts funding from the Office of Non-Proliferation and National Security), we examined the feasability of this technique, which we are referring to as PXAMS (Projectile X ray AMS), to the detection of several isotopes at Lawrence Livermore National Laboratory (LLNL). In our first exploratory work, we measured the x ray yield vs energy for {sup 80}Se ions stopped in a thick Y target. These results, demonstrated that useful detection efficiencies could be obtained for Se ions at energies accessible with our accelerator, and that the count rate from target x rays is small compared to the Se K{alpha} rate. We followed these measurements with a survey of x ray yields for Z = 14-46.

  2. Energy loss of /sup 12/C projectiles in different carbon modifications

    International Nuclear Information System (INIS)

    The stopping cross sections of the three carbon modifications diamond, graphite, and glassy carbon are investigated for carbon projectiles of intermediate velocity. The inverted Doppler-shift attenuation method was used as the experimental technique, and it enabled us to measure the ratios of the three stopping cross sections precisely over a wide energy range. For velocities between 3 and 4 times Bohr's velocity the stopping cross sections of graphite and glassy carbon are found to be 1.036 and 1.072 times larger than that of diamond, respectively. These differences are attributed to binding effects. To understand these effects, we have evaluated the mean ionization potentials utilizing the local-plasma approximation for the inner-shell electrons and the dielectric response function for the valence electrons. The theoretical ratios calculated by inserting these potentials into the Bethe-Bloch stopping-power formula agree well with our experimental results. Furthermore, we have obtained a value of 53.3 +- 4.1 fs for the lifetime of the first excited state of the /sup 12/C nucleus

  3. Study of Relativistic Nucleus-nucleus Coll.Induced by 16O Projectiles

    CERN Multimedia

    2002-01-01

    A double experiment in which two detector systems (Streamer Chamber, Plastic Ball Calorimeter), running concurrently via a beam split (West Area H3, X5), search for quark matter formation in violent collisions of |1|6O or |2|0Ne with target nuclei between |4|0Ca and |2|0|6Pb. The acceleration of |1|6O will be facilitated by a high charge state injector, consisting of an ECR source and an RFQ pre-accelerator, installed by GSI and LBL at the PS Linac 1. Experimental equipment will be a streamer chamber installed in the Vertex Magnet of experiment WA75 together with beam hodoscopes and a downstream trigger calorimeter selecting violent events by the absence of energy flow to the projectile fragmentation region. Observed particles will be p, @p, K|0, @L and @L. In addition there will be the Plastic Ball, 800-fold @DE-E particle identifier system, covering the target fragmentation and backward fireball regions. Together with a multisegmented large solid angle (@+~9|0 of beam) energy calorimeter and a trigger calor...

  4. Correlations with projectile-like fragments and emission order of light charged particles

    Science.gov (United States)

    Kohley, Z.; Bonasera, A.; Galanopoulos, S.; Hagel, K.; May, L. W.; McIntosh, A. B.; Stein, B. C.; Souliotis, G. A.; Tripathi, R.; Wuenschel, S.; Yennello, S. J.

    2012-10-01

    Correlations of midrapidity light charged particles (LCPs) and intermediate mass fragments (IMFs) with projectile-like fragments (PLFs) have been examined from the 35 MeV/u 70Zn+70Zn, 64Zn+64Zn, and 64Ni+64Ni reaction systems. A new method was developed to examine the flow of the particles with respect to the PLF. The invariant PLF-scaled flow allowed for the dynamics of the midrapidity Z=1-4 particles to be studied. Strong differences in the PLF-scaled flow were observed between the different isotopes. In particular, the most n-rich LCPs exhibited a negative PLF-scaled flow in comparison to the other LCPs. A classical molecular dynamics model and a three-body Coulomb trajectory simulation were both used to show that the PLF-scaled flow observable could be connected to the average order of emission of the LCPs. The experimental results suggest that the midrapidity region is preferentially populated with neutron-rich LCPs and Z=3-4 IMFs at a relatively early stage in the collision. The deuteron and 3He particles are emitted later followed, lastly, by protons and alphas. The average order of emission of the midrapidity LCPs was extracted from the constrained molecular dynamics simulations and showed good agreement with the emission order suggested by the experimental PLF-scaled flow results.

  5. Parameterization of fusion barriers for light-projectiles-induced reactions using the proximity approach

    Energy Technology Data Exchange (ETDEWEB)

    Gharaei, R. [Hakim Sabzevari University, Department of Physics, Sciences Faculty, P. O. Box 397, Sabzevar (Iran, Islamic Republic of); Sheibani, J. [University of Birjand, Department of Physics, Ferdows Faculty of Engineering, Ferdows (Iran, Islamic Republic of)

    2016-05-15

    In this article we propose a pocket formula for fusion barriers calculated by three versions of the proximity formalism, namely AW 95, Bass 80 and Prox. 2010 potentials, for fusion reactions involving the collisions of the proton and helium projectiles with different targets in mass ranges 51≤ A{sub T}≤130 and 40≤A{sub T}≤233, respectively. For the first type of the colliding systems, it is shown that the proposed pocket formulas are able to predict the actual values of R{sub B} and V{sub B} within accuracies of ±0.4% and ±0.45%, respectively. Moreover, for the second type of the selected reactions, these accuracies are obtained ±0.24% and ±0.36%, respectively. In this study, the ability of the present pocket formulas is also demonstrated to predict the exact values of the fusion cross sections for our selected mass ranges. A comparison with the results of the previous pocket formulas reveals that our parameterized forms are more successful to reproduce the empirical data of the barrier height and position in the proton- and helium-induced reactions. (orig.)

  6. Observation of anomalous reaction mean free paths of nuclear-projectile fragments in research emulsion from 2 A GeV heavy-ion collisions

    International Nuclear Information System (INIS)

    From an analysis of 1460 projectile fragment collisions in nuclear research emulsion exposed to 2.1 A GeV 16O and 1.9 A GeV 56Fe at the Bevalac, evidence is presented for the existence of an anomalously short interaction mean free path of projectile fragments for the first several cm after emission. The result is significant to beyond the 3 standard deviation confidence level

  7. Development of an objective method for the comparison of fired projectiles using an air pistol as a template.

    Science.gov (United States)

    Hamzah, Noor Hazfalinda

    2016-07-01

    The ability to objectify ballistic evidence is a challenge faced by firearms examiners around the world. A number of researchers are trying to improve bullet-identification systems to address deficiencies detailed within the National Academy of Science report (2009). More recently focus has turned to making use of more sophisticated imaging modalities to view entire regions of the projectile and the development of automated systems for the comparison of the topographical surfaces recorded. Projectiles from a newly bought air pistol with 0.177 calibre pellets (unjacketed), fired series of 609 pellets were examined using an optical microscope. A mathematical methodology was developed to pre-process the resultant topographical maps generating point data for comparison, analysed using the principal component analysis (PCA). In most cases limited to reasonable success was achieved. The objective method still requires an operator to identify the Land Engraved Areas to be scanned, however the mathematical alignments were objectively achieved. The PCA results illustrated that the striation marks were neither exclusive nor specific to the LEA regions but rather crossed over regions. This study also proves that a single weapon does not necessarily leave identical marks of projectiles on its surface. PMID:27081766

  8. 弹丸阻尼片特性研究%Research Property of Damp Tab for Projectile

    Institute of Scientific and Technical Information of China (English)

    何光林; 李杰; 武国辉

    2008-01-01

    To reduce many factors resulted in error of projectile, a damp tap means was put forward. At first, the mechanical structure and working principle of a damp tab were introduced. Then by using MDT and Working Model 3D, the damp tab was systematically simulated and analyzed, the results of which prove the design's correctness. Additional, with hydrokinetics software to analyse the tab's liquidity, the projectile's surface airflow will not become more equably, and the projectile's head-on liquidity density will add as the attack angle increases.%为了减少多种因素造成的落点误差,提出了一种阻尼片技术.首先介绍了阻尼片的机械构造和工作原理.然后通过MDT和3D模型,阻尼片得到系统模仿和分析,试验结果表明设计的正确性.另外,通过流体动力学软件测试阻尼片的流动性,弹丸表面的气流不会变得更加稳定,而且弹丸正面气流的密度随着攻击角度的增大而增加.

  9. Penetration Evaluation of Explosively Formed Projectiles Through Air and Water Using Insensitive Munition: Simulative and Experimental Studies

    Directory of Open Access Journals (Sweden)

    M. Ahmed

    2016-02-01

    Full Text Available The process of formation, flying, penetration of explosively-formed projectiles (EFP and the effect of water on performance of the charge for underwater applications is simulated by Ansysis Autodyn 2D-Hydro code. The main objective of an explosively formed projectile designed for underwater applications is to disintegrate the target at longer standoff distances. In this paper we have simulated the explosively formed projectile from OFHC-Copper liner for 1200 conical angle. The Affect of water on the penetration of EFP is determined by simulations from Ansysis Autodyn 2-D Hydrocode and by varying depth of water from 1CD-5CD. The depth of penetration against steel target is measured experimentally. Flash X-Ray Radiography (FXR is used to capture EFP jet formation and its penetration against target is measured by depth of penetration experiments. Simulation results are compared with experimental results. The difference in simulated and experimental results for depth of penetration is about 7 mm, which lies within favorable range of error. The jet formation captured from FXR is quite clear and jet velocity determined from Flash X-ray radiography is the same as the ones obtained by using other high explosives. Therefore, it is indicated that Insensitive Munition (8701 can be utilized instead of Polymer Bonded Explosives (PBX for air and underwater environments with great reliability and without any hazard.

  10. Vomiting Larry: a simulated vomiting system for assessing environmental contamination from projectile vomiting related to norovirus infection.

    Science.gov (United States)

    Makison Booth, Catherine

    2014-09-01

    Infectious diseases such as norovirus can induce emesis (vomiting), which can be of a projectile nature. Although studies have been carried out on transmission, prevalence and decontamination of such micro-organisms within various environments, little is known about the extent to which the surrounding environment is contaminated when an individual vomits. This is an important consideration for infection control purposes. The aim of this study was to develop a simulated vomiting system (Vomiting Larry) to be used for assessing the extent to which projected fluid can contaminate the environment. Vomiting Larry was set up within a Controlled Atmosphere Chamber (CAC) facility at the Health and Safety Laboratory (HSL). Simulated vomiting was undertaken using water as a vomitus substitute containing a fluorescent marker enabling small splashes, ordinarily missed, to be visualised using UV lighting. Experiments revealed that splashes and droplets produced during an episode of projectile vomiting can travel great distances (>3 m forward spread and 2.6 m lateral spread). The research highlighted that small droplets can be hard to see and therefore cleaning all contaminated surfaces is difficult to achieve. Evidence from this study suggests that areas of at least 7.8 m(2) should be decontaminated following an episode of projectile vomiting.

  11. Computational and Experimental Investigation on Aerodynamic Characteristics of Terminally Sensitive Projectile with S-C Shaped Fins

    Institute of Scientific and Technical Information of China (English)

    HU Zhi-peng; LIU Rong-zhong; GUO Rui

    2012-01-01

    The design of terminally sensitive projectile scanning platform requires a better understanding of its aerodynamic characteristics.The terminally sensitive projectile with S-C fins has a complex aerodynamic shape,which is constructed with small length to diameter ratio cylindrical body on which two low aspect ratio fins are installed.The study focuses on the effect of fin aspect ratio on the aerodynamic characteristics.Simulation was carried on based on computational fluid dynamics(CFD) method,and the pressure distribution characteristic,drag coefficient,lift coefficient and rolling moment coefficient varying with attack angle were obtained.A free flying experimental investigation focused on the kinetic aerodynamics was made.The results show that the fins provide sufficient drag to balance the terminally sensitive projectile weight to keep it flying at low and stable speed.The lift coefficient has a negative linear varying with attack angle.The rolling moment decrease with the increase in attack angle and the decrease in wing span area.

  12. Recent precision experiments with exotic nuclei produced with uranium projectiles and experimental prospects at FAIR

    International Nuclear Information System (INIS)

    Precision experiments with relativistic fragments separated in-flight require special experimental methods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the in- flight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A*MeV 238U ions were used to create 60 new neutron-rich isotopes separated and identified with the FRS to measure their production cross sections. In another experimental campaign the fragments were separated in flight and injected into the storage-cooler ring ESR for accurate mass and lifetime measurements. In these experiments we have obtained accurate new mass values analyzed via a novel method which has reduced the systematic errors for both Schottky Mass Spectrometry (SMS) and for Isochronous Mass Spectrometry (IMS). Pioneering experiments have been carried out with the FRS Ion Catcher consisting of 3 experimental components, the dispersive magnetic system of the FRS with a monoenergetic and a homogeneous degrader, a cryogenic stopping cell filled with pure helium and a multiple-reflection time-of flight mass separator. The FRS Ion Catcher enables high precision spectroscopy experiments with eV to keV exotic nuclides. Results from these different FRS experiments are presented in this overview together with prospects for the next-generation facility Super-FRS. The novel features of the Super-FRS compared with the present FRS will be discussed in addition. (authors)

  13. Recent Precision Experiments with Exotic Nuclei Produced with Uranium Projectiles and Experimental Prospects at Fair

    Directory of Open Access Journals (Sweden)

    Geissel H.

    2014-03-01

    Full Text Available Precision experiments with relativistic fragments separated in-flight require special experimentalmethods to overcome the inherent large emittance from the creation in nuclear reactions and atomic interactions in matter. At GSI relativistic exotic nuclei have been produced via uranium projectile fragmentation and fission and investigated with the inflight separator FRS directly, or in combination with either the storage-cooler ring ESR or the FRS Ion Catcher. 1000 A·MeV 238U ions were used to create 60 new neutron-rich isotopes separated and identified with the FRS to measure their production cross sections. In another experimental campaign the fragments were separated in flight and injected into the storage-cooler ring ESR for accurate mass and lifetime measurements. In these experimentswe have obtained accurate new mass values analyzed via a novel method which has reduced the systematic errors for both Schottky Mass Spectrometry (SMS and for Isochronous Mass Spectrometry (IMS. Pioneering experiments have been carried out with the FRS Ion Catcher consisting of three experimental components, the dispersive magnetic system of the FRS with a monoenergetic and a homogeneous degrader, a cryogenic stopping cell filled with pure helium and a multiple-reflection time-of flight mass separator. The FRS Ion Catcher enables high precision spectroscopy experiments with eV to keV exotic nuclides. Results from these different FRS experiments are presented in this overview together with prospects for the next-generation facility Super-FRS. The novel features of the Super-FRS compared with the present FRS will be discussed in addition.

  14. Damage production in low-energy Au and Si irradiation of a-Si: Influence of projectile mass

    CERN Document Server

    Koster, M

    2003-01-01

    Using molecular-dynamics computer simulation, we study the processes occurring in a-Si after irradiation with a projectile with energy E sub 0<=500 eV. By comparing Au and Si impact, we can study the effects of high and low deposited energy density. We find that damage production (creation of over- and under-coordinated Si atoms) and recoil implantation are strongly enhanced under Au impact. This effect can be traced back to the creation of an elastic collision spike for Au impact.

  15. Projectile- and charge-state-dependent electron yields from ion penetration of solids as a probe of preequilibrium stopping power

    DEFF Research Database (Denmark)

    Rothard, H.; Schou, Jørgen; Groeneveld, K.-O.

    1992-01-01

    Kinetic electron-emission yields gamma from swift ion penetration of solids are proportional to the (electronic) stopping power gamma approximately Beta-S*, if the preequilibrium evolution of the charge and excitation states of the positively charged ions is taken into account. We show...... theory after having presented a summary of recent results on the projectile- and charge-state dependence of forward and backward electron yields gamma(F) and gamma(B) and the Meckbach factor R = gamma(F)/gamma(B). A simple extension of the yield equations is proposed and several assumptions are justified...

  16. Elastic break-up of 156 MeV 6Li projectiles with large asymptotic relative momenta of the fragments

    International Nuclear Information System (INIS)

    The triple differential cross sections for elastic break-up of 156 MeV 6Li projectiles by the reactions 208Pb (6Li, ad) 208Pbg.s., and 12C (6Li, ad) 12Cg.s. have been measured with large asymptotic relative momenta of the outgoing fragments. The data exhibit rather unfamiliar shapes of the energy spectra, often replacing the usual bell-shape distributions by double-peaked structures and varying rapidly with the relative emission angles. The origin of these features has been explored and the cross sections have been analysed on the basis of a diffractive disintegration approach. (orig.)

  17. Geometrical aspects of reaction cross sections for {sup 3}He, {sup 4}He and {sup 12}C projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Ingemarsson, A. [Uppsala Univ. (Sweden). Dept. of Radiation Sciences; Lantz, M. [Uppsala Univ. (Sweden). The Svedberg Laboratory

    2003-04-01

    A black-disc model combined with accurate matter densities has been used for an investigation of reaction cross sections for {sup 3}He, {sup 4}He and {sup 12}C projectiles. A simple relation is derived between the energy dependence of the reaction cross sections and the strength of the nucleon-nucleon interaction. A comparison is also made of the reaction cross sections for {sup 3}He and {sup 4}He for six different nuclei {sup 12}C, {sup 16}O, {sup 40}Ca, {sup 58,60}Ni and {sup 208}Pb.

  18. Neutron-rich rare isotope production from projectile fission of heavy beams in the energy range of 20 MeV/nucleon

    CERN Document Server

    Vonta, N; Loveland, W D; Kwon, Y K; Tshoo, K; Jeong, S C; Veselsky, M; Bonasera, A; Botvina, A

    2016-01-01

    We investigate the possibilities of producing neutron-rich nuclides in projectile fission of heavy beams in the energy range of 20 MeV/nucleon expected from low-energy facilities. We report our efforts to theoretically describe the reaction mechanism of projectile fission following a multinucleon transfer collision at this energy range. Our calculations are mainly based on a two-step approach: the dynamical stage of the collision is described with either the phenomenological Deep-Inelastic Transfer model (DIT), or with the microscopic Constrained Molecular Dynamics model (CoMD). The deexcitation/fission of the hot heavy projectile fragments is performed with the Statistical Mul- tifragmentation Model (SMM). We compared our model calculations with our previous experimental projectile-fission data of 238U (20 MeV/nucleon)+208Pb and 197Au (20 MeV/nucleon)+197Au and found an overall reasonable agreement. Our study suggests that projectile fission following periph- eral heavy-ion collisions at this energy range of...

  19. A Residual Mass Ballistic Testing Method to Compare Armor Materials or Components (Residual Mass Ballistic Testing Method)

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin Langhorst; Thomas M Lillo; Henry S Chu

    2014-05-01

    A statistics based ballistic test method is presented for use when comparing multiple groups of test articles of unknown relative ballistic perforation resistance. The method is intended to be more efficient than many traditional methods for research and development testing. To establish the validity of the method, it is employed in this study to compare test groups of known relative ballistic performance. Multiple groups of test articles were perforated using consistent projectiles and impact conditions. Test groups were made of rolled homogeneous armor (RHA) plates and differed in thickness. After perforation, each residual projectile was captured behind the target and its mass was measured. The residual masses measured for each test group were analyzed to provide ballistic performance rankings with associated confidence levels. When compared to traditional V50 methods, the residual mass (RM) method was found to require fewer test events and be more tolerant of variations in impact conditions.

  20. Measurement of Low Level Explosives Reaction in Gauged Multi-Dimensional Steven Impact Tests

    Energy Technology Data Exchange (ETDEWEB)

    Niles, A M; Garcia, F; Greenwood, D W; Forbes, J W; Tarver, C M; Chidester, S K; Garza, R G; Swizter, L L

    2001-05-31

    The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and also be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times. Carbon resistor gauges indicated late time low level reactions 200-540 {micro}s after projectile impact, creating 0.39-2.00 kb peak shocks centered in PBX 9501 explosives discs and a 0.60 kb peak shock in a LX-04 disk. Steven Test modeling results, based on ignition and growth criteria, are presented for two PBX 9501 scenarios: one with projectile impact velocity just under threshold (51 m/s) and one with projectile impact velocity just over threshold (55 m/s). Modeling results are presented and compared to experimental data.

  1. The study of quasi-projectiles produced in Ni+Ni and Ni+Au collisions: excitation energy and spin; Etude des quasi-projectiles produits dans les collisions Ni+Ni et Ni+Au: energie d'excitation et spin

    Energy Technology Data Exchange (ETDEWEB)

    Buta, A

    2003-02-01

    During the collision between the projectile and the target nuclei in the intermediate energy regime (E < 100 MeV/nucleon) two excited nuclei are mainly observed in the exit channel, the quasi projectile (QP) and the quasi target. They disintegrate by particle emission. However, this binary picture is perturbed by the emission of particles and light fragments with velocities intermediate between the projectile velocity and the target one, all along the interaction (midrapidity component). This work aim to determine the excitation energy and the intrinsic angular momentum (or spin) of quasi-projectiles produced in the Ni+Ni and Ni+Au collisions at 52 and 90 MeV/nucleon. The excitation energy is deduced from the kinematical characteristics of particles emitted by the quasi-projectile. They have to be separated from midrapidity particles. Three different scenarios have been used for this purpose. The spin of the quasi-projectile has been extracted from the experimental data by mean of proton and alpha particles multiplicities emitted by the QP in the Ni+Au at 52 MeV/nucleon reaction. The results have been compared to the predictions of a theoretical model based on nucleon transfers. Their evolution is qualitatively reproduced as a function of the violence of the collision. (author)

  2. Experimental and theoretical results on electron emission in collisions between He targets and dressed Li$^{q+}$ (q=1,2) projectiles

    CERN Document Server

    Fregenal, D; Fiol, J; Fainstein, P D; Rivarola, R D; Bernardi, G; Suárez, S

    2014-01-01

    We investigate experimentally and theoretically the electron emission in collisions between He atoms and Li$^{q+}$ (q=1,2) projectiles at intermediate-high incident energies. We report on measured absolute values of double differential cross-sections, as a function of the emitted electron energy and angle, at a collision energy of 440~keV/u. The different contributions from target-ionisation, projectile-ionisation, and simultaneous target-projectile ionisation are calculated with the quantum-mechanical Continuum Distorted Wave and Continuum Distorted Wave -- Eikonal Initial State models, and with Classical Trajectory Monte Carlo simulations. There is an overall good agreement of the calculations with the experimental data for electron emission cross-sections.

  3. Rate capability of a cryogenic stopping cell for uranium projectile fragments produced at 1000 MeV/u

    Science.gov (United States)

    Reiter, M. P.; Rink, A.-K.; Dickel, T.; Haettner, E.; Heiße, F.; Plaß, W. R.; Purushothaman, S.; Amjad, F.; Ayet San Andrés, S.; Bergmann, J.; Blum, D.; Dendooven, P.; Diwisch, M.; Ebert, J.; Geissel, H.; Greiner, F.; Hornung, C.; Jesch, C.; Kalantar-Nayestanaki, N.; Knöbel, R.; Lang, J.; Lippert, W.; Miskun, I.; Moore, I. D.; Nociforo, C.; Petrick, M.; Pietri, S.; Pfützner, M.; Pohjalainen, I.; Prochazka, A.; Scheidenberger, C.; Takechi, M.; Tanaka, Y. K.; Weick, H.; Winfield, J. S.; Xu, X.

    2016-06-01

    At the Low-Energy Branch (LEB) of the Super-FRS at FAIR, projectile and fission fragments will be produced at relativistic energies, separated in-flight, energy-bunched, slowed down and thermalized in a cryogenic stopping cell (CSC) filled with ultra-pure He gas. The fragments are extracted from the stopping cell using a combination of DC and RF electric fields and gas flow. A prototype CSC for the LEB has been developed and successfully commissioned at the FRS Ion Catcher at GSI. Ionization of He buffer gas atoms during the stopping of energetic ions creates a region of high space charge in the stopping cell. The space charge decreases the extraction efficiency of stopping cells since the high amount of charge distorts the applied DC electric drag fields. Thus the understanding of space charge effects is of great importance to make full use of the high yields at future RIB facilities such as the Super-FRS at FAIR. For this purpose a detailed study of space charge effects in the CSC was performed using experiments and simulations. The dependence of the extraction efficiency, the extraction time and the temporal ion extraction profile on the intensity of the impinging beam and the electric field strength was studied for two different 238 U projectile fragments produced at 1000 MeV/u and separated with the FRS. Good agreement between experiments and simulations was found.

  4. Projectile influence on production cross section for ^48Ca-, ^50Ti-, and ^54Cr- induced fusion-evaporation reactions

    Science.gov (United States)

    Mayorov, D. A.; Werke, T. A.; Alfonso, M. C.; Bennett, M. E.; Folden, C. M., III

    2013-04-01

    Evaporation residue excitation functions for ^48Ca, ^50Ti + ^159Tb and ^48Ca, ^54Cr + ^162 Dy were measured at Texas A&M University using the vacuum spectrometer MARS. The produced residues are weakly deformed nuclei near the N = 126 shell closure. However, the production cross sections are insensitive to the associated shell stabilization to the fission barrier, an observation previously reported in literature. The ratio of maximum production cross sections between the ^48Ca/^50Ti and ^48Ca/^54Cr reactions is 47 and 7100, respectively. These substantial differences can be reproduced in theoretical calculations by inclusion of collective enhancements during de-excitation of the compound nucleus. The competition between quasifission and complete fusion further contributes to the observed separation in the excitation functions. Model-dependent estimates of the compound nucleus formation probability, PCN, yield ratios of PCN(^48Ca + ^159 Tb) / PCN(^50Ti + ^159 Tb) 2.5 and PCN(^48Ca + ^162Dy) / PCN(^54Cr + ^162Dy) 5. Heavy-ion fusion reactions with ^48Ca, ^50Ti, and ^54Cr projectiles are of interest due to modern-day efforts to synthesize superheavy elements 119 and 120 in warm fusion reactions with projectiles having Z 20.

  5. Interactions of $^{16}$O Projectile and its Fragments in Nuclear Emulsion at about 60 and 200 GeV/nucleon

    CERN Multimedia

    2002-01-01

    The aim of the experiment is to measure the multiplicity ``$ n _{s} $'' and pseudo-rapidity ``$\\eta$'' of the shower particles ($\\beta$~$\\geq$~0.7) produced in different types of collisions (peripheral, semi-central and central), of $^{16}$O and $^{32}$S in nuclear emulsions. The multiplicities and angular distributions of both the grey ``$ n _{g} $'' (mainly due to knock- on and recoil protons), and black ``$ n _{b} $'' (slow evaporated target fragments) particles, and the inter-correlation between them are studied. \\\\ \\\\ The yield, charge and angular distributions of produced relativistic projectile fragments P.F.S., for $ Z _{P} . _{F} . $ $\\geq$~2 are measured and their interactions in emulsions are investigated. \\\\ \\\\ The study of the mean free paths for the projectile fragments with Z $\\geq$ 3 produced from 200~A~GeV $^{16}$ 0 interactions were performed, which show the absence of the anomalous phenomena. \\\\ \\\\ The possible production of zero-spin light neutral scaler bosons and pseudoscaler bosons from...

  6. Multiplicity distributions of projectile fragments in interactions of nuclei with emulsion at 4.1-4.5 A GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Fakhraddin, S; Rahim, Magda A [Physics Department, Faculty of Science, Sana' a University, Republic of Yemen (Yemen)], E-mail: sakinafa1@hotmail.com, E-mail: dr.magda2006@hotmail.com

    2008-07-15

    The results of our systematic studies of projectile fragments (PFs) multiplicity distributions in interactions of {sup 4}He, {sup 12}C, {sup 16}O, {sup 22}Ne and {sup 28}Si with emulsion at 4.1-4.5 A GeV/c are presented in this paper. The mean values for the three different multiplicities of PFs at nearly the same energy are given. The dependence of these mean values on the projectile mass number A{sub p}, as well as the dependence of the PFs on target groups (H, CNO and AgBr), has been investigated.

  7. Systematic study of projectile fragments in nucleus-nucleus collisions at 4.1-4.5 A GeV/c and multi-source thermal model

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, M.A.; Fakhraddin, S.; Asharabi, H. [Sana' a University, Physics Department, Faculty of Science, Sana' a (Yemen)

    2012-08-15

    The multiplicity distributions of projectile fragments (PFs) produced in interactions of ({sup 4}He, {sup 12}C, {sup 16}O, {sup 22}Ne and {sup 28}Si) with emulsion (Em) at 4.1-4.5 A GeV/c beam energies, and their dependence on target groups (H, CNO and AgBr) are presented and have been reproduced by using a multi-source thermal model. The dependence of the mean multiplicities on masses of projectile and target nuclei is investigated. The experimental results are compared with the corresponding ones from the theoretically calculated ones. The experimental results agree with theoretical calculations using the multi-source thermal model. (orig.)

  8. Role of nucleon-nucleon collisions in peripheral nuclear reactions near 30 MeV/A. Study of neutrons/projectile-like fragment correlations in the 20Ne + 165Ho reaction at 30 MeV/A

    International Nuclear Information System (INIS)

    Correlations between projectile-like fragments (4 ≤ Z 20Ne + 165Ho reaction at 30 MeV/A have been measured. Projectile-like fragments emitted at ± 80 were detected with two silicon detectors. Coincident neutrons were detected with 10 NE213 scintillators set between -1400 and +1400. Projectile-like fragment energy spectra and neutron velocity and multiplicity distributions were thus obtained. As a function of the charge and energy of the projectile-like fragment, neutron velocity spectra were analysed using three moving sources: a projectile-like source, a target-like source and an intermediate velocity source. Experimental results were compared with predictions of a statistical model, based on nucleon-nucleon collisions (code PERCUT), the de-excitation of primary products being treated by statistical evaporation models (codes LANCELOT and EVAP). For low linear momentum transfer collisions, experimental results are in good agreement with theoretical predictions

  9. Electron correlations in single-electron capture into any state of fast projectiles from heliumlike atomic systems

    Science.gov (United States)

    Mančev, Ivan; Milojević, Nenad; Belkić, Dževad

    2013-11-01

    State-selective and total single-electron capture cross sections in fast collisions of a bare projectile with a heliumlike target are examined in the four-body formalism. A special emphasis is given to a proper inclusion of dynamic electron-electron correlation effects. For this purpose, the post form of the four-body boundary-corrected first Born approximation (CB1-4B) is utilized. With regard to our related previous study, where the prior version has been considered, in the present work an extensive analytical study of the post-transition amplitude for electron capture into the arbitrary final states nflfmf of the projectile is carried out. The post-transition amplitude for single charge exchange encompassing symmetric and asymmetric collisions is derived in terms of five-dimensional integrals over real variables. The dielectronic interaction V12=1/r12≡1/|r⃗1-r⃗2| explicitly appears in the perturbation potential Vf of the post-transition probability amplitude Tif+, such that the CB1-4B method can provide information about the relative significance of the dynamic interelectron correlation in the collisions under study. An illustrative computation is performed involving state-selective and total single capture cross sections for the p-He collisions at intermediate and high impact energies. The so-called post-prior discrepancy, which plagues almost all the existing distorted wave approximations, is presently shown to be practically nonexistent in the CB1-4B method. The validity of our findings is critically assessed in comparisons with the available experimental data for both state-selective and total cross sections summed over all the discrete energy levels of the hydrogenlike atom formed with the projectile. Overall, excellent performance of the CB1-4B method is recorded, thus robustly establishing this formalism as the leading first-order description of high-energy single charge exchange, which is a collision of paramount theoretical and practical

  10. Projectile energy dependence in the molecular excitation of th H3+, D3+ molecular ions in their polar dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Yousif, F.B.; Hinojosa, G.; Dominguez, I. [IFUNAM, Cuernavaca (Mexico)] [and others

    1996-05-01

    The laboratory energy distributions of H{sup +} and D{sup +} in coincidence with H{sup {minus}} and D{sup {minus}} ions, resulting from the collision-induced-dissociation of H{sup 3+} and D{sup 3+} on He target for incoming beam energies ranging from 2.5 to 9.0 keV has been measured. The energy-analyzed-spectra of ionic fragments were measured both independently and in coincidence with each other. From these, the energy absorbed by the dissociating molecular ions in the excitation process induced by the collision with He prior to its breakup, was evaluated as a function of the projectile energy and it was found that it is not constant but it is consistent with the identified H{sup 3+} excited states which have adiabatic Born-Oppenheimer energies of 21-50 eV above the H{sup 3+} ground state.

  11. Projectile energy dependence in the molecular excitation of th H3+, D3+ molecular ions in their polar dissociation

    International Nuclear Information System (INIS)

    The laboratory energy distributions of H+ and D+ in coincidence with H- and D- ions, resulting from the collision-induced-dissociation of H3+ and D3+ on He target for incoming beam energies ranging from 2.5 to 9.0 keV has been measured. The energy-analyzed-spectra of ionic fragments were measured both independently and in coincidence with each other. From these, the energy absorbed by the dissociating molecular ions in the excitation process induced by the collision with He prior to its breakup, was evaluated as a function of the projectile energy and it was found that it is not constant but it is consistent with the identified H3+ excited states which have adiabatic Born-Oppenheimer energies of 21-50 eV above the H3+ ground state

  12. Influence of the neutron numbers of projectile and target on the evaporation residue cross sections in hot fusion reactions

    Science.gov (United States)

    Zhu, Long; Su, Jun; Zhang, Feng-Shou

    2016-06-01

    Within the framework of a dinuclear system model, the influence of projectile and target neutron number on capture cross section, fusion probability, and survival probability for the reactions S,3634+238U and 48Ca+Pu 239 ,240 ,242 ,244 are investigated. The calculated excitation functions are in good agreement with the experimental data. To synthesize more unknown neutron-deficient isotopes of already-known superheavy elements, the possibility of using lighter calcium isotopes to induce hot fusion reactions is investigated and the maximal evaporation residual cross sections for Ca 44 ,46 ,48 -induced hot fusion reactions to produce unknown neutron-deficient superheavy nuclei with Z =112 -116 are predicted.

  13. Measurements in the beam direction of the 40Ar projectile fragmentation at 44 MeV/A

    International Nuclear Information System (INIS)

    Accurate beam direction measurements (0±3mr) have been performed on the 40Ar projectile fragmentation on a Ni target, at 44 MeV/u, by using the telescopic mode on the double spectrometer LISE at GANIL. Sampling results on Al and Au targets are also presented. Velocity distributions are analysed for fragments of masses from 10 to 45. As expected from a study of the forward angle physics, the presented beam direction measurements (0 deg) and the grazing angle ones (3 deg) exhibit spectacular differences. The most probable velocities are found much closer to the beam one at 0 deg than at 3 deg. The velocity-integrated mass-yields obtained in the beam direction exhibit a regular exponential rise from A ∼ 18 to A ∼ 40. The role of diffraction is to be examined. (author) 24 refs., 13 figs., 2 tabs

  14. Ion desorption phenomena induced by various types of multiply charged projectiles and by photons on solid surfaces

    International Nuclear Information System (INIS)

    Ion desorption experiments are described in two regions of primary ion velocities corresponding to two distinct classes of interaction mechanism. At low speeds, atomic collisions take place, at higher speeds than the electron velocity, electronic collisions occur. Experiments with fast ions above 0.2 MeV/u are described, using 32S and 235U ions obtained in a cyclotron and a linear accelerator. Emission of H+ ions from solid surfaces is measured and analyzed, and applied to the determination of the charge state of a fast ion in a solid. Experiments using single atomic and polyatomic, keV ions, and organic and CsI cluster ions as projectiles are also presented. Finally, laser desorption is discussed. (R.P.) 81 refs., 27 figs., 2 tabs

  15. The unified description of direct and resonant excitations of the nucleus 40Ca by medium-energy projectiles

    International Nuclear Information System (INIS)

    In the framework of a unified theory of direct and resonant reactions the excitation of 40Ca by medium-energy projectiles has been investigated. The applied 1p-1h approximation turns out to be capable of describing the gross features of the measured spectra. A considerable part of the smooth background is found to be produced by resonance transitions. A dominant g/sub 9/2/(1d/sub 5/2/)-1 structure of the giant quadrupole resonance is proposed, which is in agreement with the observed decay channels. The importance of high-lying single-particle states with large angular momentum 1 > 3 is emphasized, in particular for reactions with hadrons. It is shown that coincidence experiments are suitable for suppressing the background. (author)

  16. Deuteron - $\\alpha$ interaction by inversion of RGM S-matrix determination of spin-orbit potential for spin-1 projectile

    CERN Document Server

    MacIntosh, R S

    1997-01-01

    The iterative-perturbative (IP) procedure for S-matrix to potential inversion is applied to spin-one projectiles for the restricted case of vector spin-orbit interaction only. In order to evaluate this extension of IP inversion we have inverted the multi-channel RGM $S_{lj}$ of Kanada et al for deuterons scattering from $^4$He with deuteron distortion and then compared the central components with those derived from RGM with spin set to zero. Attention is given to the question of how well the resulting potentials are established. Reliable spin-1 inversion is demonstrated. Results relating to inversion, to deuteron-nucleus interactions and to RGM are presented and suggest the range of nuclear interaction information which the procedure makes possible. Unusual non-locality and parity dependence effects are found; these are of possible relevance to generic properties of nuclear potentials.

  17. SIMS Studies of Allende Projectiles Fired into Stardust-type Aluminum Foils at 6 km/s

    Science.gov (United States)

    Hoppe, Peter; Stadermann, Frank J.; Stephan, Thomas; Floss, Christine; Leitner, Jan; Marhas, Kuljeet; Horz, Friedrich

    2006-01-01

    We have explored the feasibility of C-, N-, and O-isotopic measurements by NanoSIMS and of elemental abundance determinations by TOF-SIMS on residues of Allende projectiles that impacted Stardust-type aluminum foils in the laboratory at 6 km/s. These investigations are part of a consortium study aimed at providing the foundation for the characterization of matter associated with micro-craters that were produced during the encounter of the Stardust space probe with comet 81P/Wild 2. Eleven experimental impact craters were studied by NanoSIMS and eighteen by TOF-SIMS. Crater sizes were between 3 and 190 microns. The NanoSIMS measurements have shown that the crater morphology has only a minor effect on spatial resolution and on instrumental mass fractionation. The achievable spatial resolution is always better than 200 nm, and C- and O-isotopic ratios can be measured with a precision of several percent at a scale of several 100 nm, the typical size of presolar grains. This clearly demonstrates that presolar matter, provided it survives the impact into the aluminum foil partly intact, is recognizable even if embedded in material of Solar System origin. TOF-SIMS studies are restricted to materials from the crater rim. The element ratios of the major rockforming elements in the Allende projectiles are well characterized by the TOF-SIMS measurements, indicating that fractionation of those elements during impact can be expected to be negligible. This permits information on the type of impactor material to be obtained. For any more detailed assignments to specific chondrite groups, however, information on the abundances of the light elements, especially C, is crucial.

  18. Rocket Projectile Detection Information Analysis System%火箭弹检测信息分析系统

    Institute of Scientific and Technical Information of China (English)

    范志锋; 崔平; 文健; 徐敬青

    2014-01-01

    In allusion to the problem of using detection information of factory and army past years to receive the variation law of the control system electrical capability of a type of rocket projectile, developing a rocket projectile detection information analysis system based on mixed programming of PB/Matlab/SQL Server/Excellis put forward. Overall function, development tools and technology and design of development function module of the system are introduced. Some basically sport technique segments of design and implementation of the system are mainly explained and the main characteristics of the system are analyzed. It is shown by the application that the system has virtues of good interface, universality, operability and easy to maintain. The system has solved the problems of management, analysis and plotting of mass detection information.%针对利用出厂检测信息和部队历年检测信息得到火箭弹控制系统电性能变化规律存在的难题,提出基于PB/Matlab/SQL Server/Excel 混合编程开发火箭弹检测信息分析系统。介绍系统总体功能、开发工具与技术、开发功能模块设计,重点对系统开发与实现的一些主要技术环节进行说明,并分析系统主要特点。应用结果表明:该系统界面友好,通用性、可操作性强,易于维护,能高效解决海量检测信息管理、分析和绘图等问题。

  19. Experiments and Theoretical Analyses on HSFRC Target Under the Impact of Rigid Projectile%HSFRC靶体的弹体侵彻试验与理论分析

    Institute of Scientific and Technical Information of China (English)

    吴昊; 方秦; 龚自明

    2012-01-01

    为了研究高强纤维增强混凝土(HSFRC)材料的抗侵彻性能,采用2种不同弹头形状的刚性动能侵彻弹,对高强钢纤维增强混凝土和高强聚丙烯纤维增强混凝土靶体进行了侵彻试验和理论分析.给出了考虑弹靶摩擦阻力和弹头形状变化的混凝土靶体侵彻深度计算公式和侵彻试验数据,基于此,拟合得到了高强混凝土靶体经验强度参数的计算表达式并进行了试验验证,弥补了经典FORRESTAL公式中强度参数适用范围低于100MPa的不足.通过对比公式计算结果和试验数据,验证了文中提出的公式和分析方法对于弹体侵彻高强纤维增强混凝土靶体深度的计算较FORRESTAL公式有更广的应用范围和更高的预测精度.%To study the anti-penetration performances of the high-strength fiber reinforced concrete(HSFRC), the field penetration tests and theoretical analyses on high-strength steel-fiber reinforced concrete (HSSFRC) and high-strength polypropylene-fiber reinforced concrete (HSPFRC) targets hit by two different nosed kinetic-energy penetrators were carried out, respectively. Considering the friction drag between projectile and target and the shape variation of warhead, the calculating formula of penetration depth of concrete target and penetration test-data were presented. The expressions of high strength concrete target strength-parameter were obtained and validated by the penetration tests, which broadened the application range of classic FORRESTAL formula(less than 100 MPa). Compared with the calculation results and tests data, the proposed formula and approaches for the prediction of depth of penetration(DOP) of HSFRC target have wider application range and higher prediction accuracy than FORRESTAL formula.

  20. An Experimental Study of Thin Steel Plates Perforated by Conical-Nosed Projectiles%锥头弹丸穿透薄钢板的实验研究

    Institute of Scientific and Technical Information of China (English)

    孙炜海; 鞠桂玲; 陈德民; 杨班权

    2012-01-01

    Both quasi-static and impact loading experiments of thin steel plates are performed using conical-nosed projectiles with cone angle of 90°. Load-deflection curves and different failure modes are acquired from the quasi-static tests. Membrane analysis and plastic collapse model with pure bending are investigated and compared with the experimental data. It is shown that the membrane force dominates the deformation process for the large deformation of thin plate~with increase of the thickness of plate, the bending moment becomes more and more important. In the impact experiments, the initial and residual velocities with different failure modes are obtained for four plates with different thicknesses, and the critical perforation energies are evaluated. In addition, the experimental data of quasi-static and dynamic tests are compared and discussed.%为了研究延性薄靶的穿透性能,进行了90°锥头弹丸穿透薄钢板的准静态和动态实验。通过准静态实验,得到了4种不同厚度钢板的载荷一压入位移曲线及破坏模式;结合膜力理论模型及纯弯静塑性破坏模型,对实验结果进行了分析,得出:对于薄靶,大变形膜力起主导作用,随着靶厚增加,弯距在板整体变形过程中的影响逐渐增大。通过动态穿透实验,得到了弹丸穿透4种不同厚度钢板的入射速度、残余速度及靶板破坏模式,计算得到穿透耗能。最后,将准静态实验与动态实验结果进行了对比讨论。

  1. Saturation effect in projectile- and target- x-ray production in collisions between 2.5 MeV/u highly charged Cu ions and gaseous targets

    Science.gov (United States)

    Kumar, Ajay; Misra, D.; Kelkar, A. H.; Kadhane, U.; Singh, Y. P.; Lapicki, G.; Gulyas, L.; Tribedi, L. C.

    2006-01-01

    L x-ray production cross sections have been measured for highly charged 2.5 MeV/u Cuq+ (q = 20-26) ions colliding with H2, Ne, Ar, Kr and Xe target atoms. The observed Cu L x-rays are due to the excitation and electron-transfer processes. The charge state dependence of the projectile L x-rays has been studied with Ar and Kr targets. We have derived the subshell resolved K-L1, K-L2 and K-L3 electron-transfer cross sections from the measured Ar K x-ray yields as a function of L vacancies in Cu ion. The measured projectile L x-ray production cross sections arising from the excitation and electron capture are found to saturate as target atomic number Zt increases. Similarly, a saturation has also been found in the Ar K-shell ionization cross sections as a function of Zp.

  2. Fragmentation of nuclei as a function of centrality of collision in interactions of gold projectiles at 10.6 A GeV

    CERN Document Server

    Dabrowska, A; Olszewski, A; Szarska, M; Trzupek, A; Wilczynska, B; Wilczynski, H; Wolter, W; Wosiek, B; Wozniak, K

    2001-01-01

    We have studied the fragmentation of light (C/N/O) and heavy (Ag/Br) nuclei of emulsion in collisions with gold projectiles at 10.6 A GeV and the fragmentation of these gold nuclei in collisions with hydrogen, (C/N/O) and (Ag/Br) nuclei. The analysis was restricted to the investigation of the number of fragments and in some cases the total charge of fragments as a function of the centrality of collisions with nuclei of different masses. We observe a decrease in the number of target fragments with increasing centrality for interactions of projectiles with masses comparable or greater than the mass of the target nucleus. As the collision becomes more central a significant number of participating protons from the target nucleus get enough momentum to become relativistic due to intranuclear interactions. These results have been compared with the predictions of the RQMD model.

  3. DYNAMIC RESPONSE OF A RIGID,PERFECTLY PLASTIC FREE-FREE BEAM STRUCK BY A PROJECTILE ATANY CROSS-SECTION ALONG ITS SPAN

    Institute of Scientific and Technical Information of China (English)

    YangJialing; LiuXuhong

    2004-01-01

    The rigid, perfectly plastic dynamic response of a free-free beam subjected to impact by a projectile at any cross-section is studied. The instantaneous deformations of the beam are given through an analysis of the complete solution for rigid plastic structures. The influence of some parameters such as the input energy and mass ratio on the plastic deformation, travelling plastic hinge position and energy partitioning of the beam are discussed.

  4. Human body projectiles implantation in victims of suicide bombings and implications for health and emergency care providers: the 7/7 experience

    OpenAIRE

    Patel, HDL; Dryden, S; Gupta, A; Stewart, N.

    2012-01-01

    INTRODUCTION On 7 July 2005 four suicide bombings occurred on the London transport systems. In some of the injured survivors, bone fragments were embedded as biological foreign bodies. The aim of this study was to revisit those individuals who had sustained human projectile implantation injuries as a result of the bomb blasts at all scenes, review the process of body parts mapping and DNA identification at the scene, detail the management of such injuries and highlight the protocols that have...

  5. Flash X-ray cinematography analysis of dwell and penetration of small caliber projectiles with three types of SiC ceramics

    Directory of Open Access Journals (Sweden)

    Elmar Strassburger

    2016-06-01

    Full Text Available In order to improve the performance of ceramic composite armor it is essential to know the mechanisms during each phase of the projectile–target interaction and their influence on the penetration resistance. Since the view on the crater zone and the tip of a projectile penetrating a ceramic is rapidly getting obscured by damaged material, a flash X-ray technique has to be applied in order to visualize projectile penetration. For this purpose, usually several flash X-ray tubes are arranged around the target and the radiographs are recorded on film. At EMI a flash X-ray imaging method has been developed, which provides up to eight flash radiographs in one experiment. A multi-anode 450 kV flash X-ray tube is utilized with this method. The radiation transmitted through the target is then detected on a fluorescent screen. The fluorescent screen converts the radiograph into an image in the visible wavelength range, which is photographed by means of a high-speed camera. This technique has been applied to visualize and analyze the penetration of 7.62 mm AP projectiles into three different types of SiC ceramics. Two commercial SiC grades and MICASIC (Metal Infiltrated Carbon derived SiC, a C-SiSiC ceramic developed by DLR, have been studied. The influences, not only of the ceramic but also the backing material, on dwell time and projectile erosion have been studied. Penetration curves have been determined and their relevance to the ballistic resistance is discussed.

  6. Research on critical behaviour during fragmentation of the projectile in the Xe+Sn (at 50 MeV/A) reaction; Recherche d`un comportement critique dans la fragmentation du projectile dans la reaction Xe+Sn a 50 MeV/A

    Energy Technology Data Exchange (ETDEWEB)

    Benlliure, J.

    1995-03-01

    The study of moments of fragments charge distributions produced in heavy ions collisions can give us evidence of a critical behavior of nuclear matter which could explain the multifragmentation pattern. From an experimental point of view, in order to perform this capabilities of the INDRA detector has made it possible to identify all these particles and to reconstruct the initial projectile-like fragment coming from binary collisions in the reaction Xe+Sn at 50 MeV/A. We have selected events where the initial projectile-like fragments keep their entire charge in a large range of excitation energy. The study of these fragment`s characteristics show clearly a change in the deexcitation pattern. The evolution of moments of the fragment charge distributions has been reproduced within a percolation model, in this sense we can interpreter this change in the deexcitation pattern as a function of the initial projectile-like fragment`s size shows the existence of finite-size effects. However, the signature of a phase transition remains independent on the projectile-like fragment`s size. (author). 74 refs., 58 figs., 9 tabs.

  7. Ballistic Performance of Coconut Shell Powder/Twaron Fabricagainst Non-armour Piercing Projectiles

    Directory of Open Access Journals (Sweden)

    M.S. Risby

    2008-03-01

    Full Text Available Body armour technologists over the years are seeking to develop protective systems whichare both effective and lightweight. However these hard armour materials are very expensive andhave certain weight constraints. From this point of view, natural fibres and fillers have attractedthe attention of researchers due to their low density with high specific strengths, abundance,availability, renewability and being environmental-friendly. This paper reports the potential useof coconut shell powder-epoxy composite (COEX panel bonded with Twaron CT716 fabric asa hard armour material and the characteristics of its fracture imprints from a specific threat levelwhen subjected to ballistic tests1 (NIJ Standard 0108.01. It was observed that the imprint patternson the particulate composite (COEX could be identified according to effectiveness in impactenergy dissipation. COEX/Twaron test panel was found to withstand impact equivalent to NIJLevel IIIA using 9 mm FMJ ammunition but perforated at NIJ Level III of 7.62 mm FMJ bulletimpacts. Test results showed that COEX panel do possess shock absorbance characteristics andcan be utilised as  an armour component in the hard-body armour system. Dependency onTwaron fabric layers as ballistic reinforcements has been reduced up to 3-time with 170 per centimprovement on energy-absorption capabilities when using COEX composite as the frontalcomponent of the armour.

  8. Ballistic behavior of high hardness perforated armor plates against 7.62 mm armor piercing projectile

    International Nuclear Information System (INIS)

    Highlights: • High hardness perforated plates can be used effectively in ballistic protection. • Perforated plate has potential of decreasing areal mass efficiency dramatically. • The defeating mechanism of multilayer perforated plates includes three principles. • Deviation from trajectory, core fracture and nose erosion are defeating mechanisms. • With the simulations and tests, the bullet defeating mechanism has been explained. - Abstract: In this paper, some of the important defeating mechanisms of the high hardness perforated plates against 7.62 × 54 armor piercing ammunition were investigated. The experimental and numerical results identified three defeating mechanisms effective on perforated armor plates which are the asymmetric forces deviates the bullet from its incident trajectory, the bullet core fracture and the bullet core nose erosion. The initial tests were performed on the monolithic armor plates of 9 and 20 mm thickness to verify the fidelity of the simulation and material model parameters. The stochastic nature of the ballistic tests on perforated armor plates was analyzed based on the bullet impact zone with respect to holes. Various scenarios including without and with bullet failure models were further investigated to determine the mechanisms of the bullet failure. The agreement between numerical and experimental results had significantly increased with including the bullet failure criterion and the bullet nose erosion threshold into the simulation. As shown in results, good agreement between Ls-Dyna simulations and experimental data was achieved and the defeating mechanism of perforated plates was clearly demonstrated

  9. Study on Titanium Alloy TC4 Ballistic Penetration Resistance Part Ⅰ: Ballistic Impact Tests

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tao; CHEN Wei; GUAN Yupu; GAO Deping

    2012-01-01

    Ballistic impact test of different-scale casings is an efficient way to demonstrate the casing containment capability at the preliminary design stage of the engine.For the sake of studying the titanium alloy TC4 casing performance,the ballistic tests of flat and curved simulation casing are implemented by using two flat blades of different sizes as the projectile.The impact mechanism and failure of the target are discussed.Impact of the projectile is a highly nonlinear transient process with the large deformation of the target.On the impact,failures of the flat casing and the subscale casing are similar,concluding two parts,the global dishing and localized ductile tearing.The main localized failure mode combines plugging (shear) and petaling (shear) if the projectile perforates or penetrates,while crater (shear) if the projectile rebounds.The ballistic limit equation is verified by the test data and the results show that this empirical equation could be a practical way to estimate the critical velocity.

  10. Study of 84Kr36 projectile fragments with compound multiplicity at ∼1 A GeV

    International Nuclear Information System (INIS)

    Nuclear emulsion detector (NED) has had a very long track record as particle detector and its importance has been proven through a long list of fundamental discoveries. It consists of H, CNO and silver halides (AgBr), where a latent track is formed after the passage of an ionizing particle. In the nuclear emulsion heavy ion collisions at intermediate and high energies provide to study the properties of nuclear dense matter and extreme conditions. In the last few decades, pions, kaons and recoil nucleons were the focus of the study of hadron-nucleus and nucleus-nucleus collision. These recoil target's nucleons (Grey particles) are in the medium energy (30-400 MeV), and basically these are eject-out target protons and emitted during the passage of leading particles. In the hadron-nucleus and nucleus-nucleus collision at higher energy, the new variable term introduced NC (= Ng + Ns) that is compound multiplicity. NC was introduced by Jurak and Linsheid, which represents the complete participant region of the colliding nucleus. Our earlier study of participants region with target's fragmentation and their dependency on the energy of the colliding system showed strong dependency on both parameters. Therefore it is important to study the participant region in the light of projectile fragmentation

  11. Adiabatic and sudden interaction potentials in the fusion-fission of heavy ion collisions: Asymmetric target-projectile combinations

    International Nuclear Information System (INIS)

    It is now well known that many reactions giving measurable fusion cross-sections also show a fission of the compound system formed, similar to the low energy fission of the known fissioning nuclei. Recently, both the fusion excitation functions and the mass equilibration in the fragmentation of the composite system were measured for a large number of systems with 94208Pb on different targets of 26Mg, 48Ca, 50Ti, 52Cr, 58Fe and 64Ni. From a theoretical point of view, it is relevant to ask the question: how do the colliding nuclei fuse and then why does the compound system formed fission instead of going to the ground state to give a stable system. In this Letter, we attempt to show that the fusion of asymmetric colliding nuclei is due to the overcoming of the interaction barriers in adiabatic potentials and the fission of the compound system should perhaps occur as a sudden process, like the one in the spontaneous fission phenomenon. We have made our calculations for the compound systems with 102<=Z<=110 and for the asymmetric target-projectile combinations of the experiments of Ref. 1, using the fragmentation theory whose basis is the asymmetric two-centre shell model

  12. Single differential projectile ionization cross sections d σ/dEe for 50 AMeV U28+ in the ESR storage ring

    Science.gov (United States)

    Hagmann, Siegbert; Hillenbrand, Pierre-Michel; Stoehlker, Thomas; Litvinov, Yuri; Appa-Sparc Collaboration

    2013-05-01

    The very high intensity beams of relativistic high Z ions with incident collision energies up to 2.7AGeV requested for experiments using the SIS100 synchrotron of FAIR require that 1.3 1011 ions at 2.6Hz be injected from SIS12/18 into SIS100. The needed luminosity of the beam can only be achieved for such high Z ions when - considering the space charge limit (~A/q2) - a low charge state q of the ion to be accelerated keeps the particle density at the highest feasible level. For a thorough understanding of beam loss it is imperative that the mechanisms active in projectile ionization be understood quantitatively to provide benchmarks for advancedab initio theories beyond first order. We have embarked on an experimental investigation of single differential projectile ionization cross sections d σ/dEe (SDCS) for single and multiple ionization of U28+in the ESR storage ring by measuring the electron loss to continuum (ELC) cusp at 00 with respect to the beam axis employing our imaging forward electron spectrometer. This was motivated by the high relative fraction of multiple ionization estimated to exceed 40%. We report first results for absolute projectile ionization SDCS for U28+. We find a remarkably high asymmetry for the ELC cusp. This is at strong variance with the line shape expected for validity of first order theories.

  13. Study of uranium dioxyde sputtering induced by multicharged heavy ions at low and very low kinetic energy: projectile charge effect; Etude de la pulverisation du dioxyde d'uranium induite par des ions lourds multicharges de basse et tres basse energie cinetique; effet de la charge du projectile

    Energy Technology Data Exchange (ETDEWEB)

    Haranger, F

    2003-12-01

    Ion beam irradiation of a solid can lead to the emission of neutral or ionized atoms, molecules or clusters from the surface. This comes as a result of the atomic motion in the vicinity of the surface, induced by the transfer of the projectile energy. Then, the study of the sputtering process appears as a means to get a better understanding of the excited matter state around the projectile trajectory. In the case of slow multicharged ions, a strong electronic excitation can be achieved by the projectile neutralization above the solid surface and / or its deexcitation below the surface. Parallel to this, the slowing down of such ions is essentially related to elastic collision with the target atoms. The study of the effect of the initial charge state of slow multicharged ions, in the sputtering process, has been carried out by measuring the absolute angular distributions of emission of uranium atoms from a uranium dioxide surface. The experiments have been performed in two steps. First, the emitted particles are collected onto a substrate during irradiation. Secondly, the surface of the collectors is analyzed by Rutherford Backscattering Spectrometry (RBS). This method allows the characterization of the emission of neutrals, which are the vast majority of the sputtered particles. The results obtained provide an access to the evolution of the sputtering process as a function of xenon projectile ions charge state. The measurements have been performed over a wide kinetic energy range, from 81 down to 1.5 keV. This allowed a clear separation of the contribution of the kinetic energy and initial projectile charge state to the sputtering phenomenon. (author)

  14. Numerical and experimental study of the impact of small caliber projectiles on ballistic soap

    Science.gov (United States)

    Ndompetelo, N.; Viot, P.; Dyckmans, G.; Chabotier, A.

    2006-08-01

    In previous studies [1, 2], an elastoplastic model for soap material has been considered to characterize the soap behavior under impacts of spherical bullets. The characterization and validation of this model were made via the deceleration of a bullet into the soap material. In order to take into account the strain hardening and strain rate effects, an investigation of an elastoviscoplastic model is made. For model characterization purposes, experimental data were obtained from the viscoelastic Hopkinson pressure bar. The model parameters were determined through an optimization process and validation of the model was done by using a series of firing tests from previous experiments where spherical bullets were fired into soap blocks [1, 2].

  15. Materials science. Dynamic mechanical behavior of multilayer graphene via supersonic projectile penetration.

    Science.gov (United States)

    Lee, Jae-Hwang; Loya, Phillip E; Lou, Jun; Thomas, Edwin L

    2014-11-28

    Multilayer graphene is an exceptional anisotropic material due to its layered structure composed of two-dimensional carbon lattices. Although the intrinsic mechanical properties of graphene have been investigated at quasi-static conditions, its behavior under extreme dynamic conditions has not yet been studied. We report the high-strain-rate behavior of multilayer graphene over a range of thicknesses from 10 to 100 nanometers by using miniaturized ballistic tests. Tensile stretching of the membrane into a cone shape is followed by initiation of radial cracks that approximately follow crystallographic directions and extend outward well beyond the impact area. The specific penetration energy for multilayer graphene is ~10 times more than literature values for macroscopic steel sheets at 600 meters per second.

  16. Ballistic Performance of Alumina and Zirconia-toughened Alumina Against 7.62 Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    S G. Savio

    2014-09-01

    Full Text Available A study was carried out to compare the ballistic performance of high purity alumina and zirconia-toughened alumina (ZTA using depth of penetration (DoP test configuration against 7.62 mm armour piercing (AP ammunition. The effect of tile thickness on the differential efficiency factor (DEF was studied for tile thickness in the range of 3 mm to 6 mm for alumina tiles and 3 mm to 5 mm for ZTA tiles. The DEF is found to increase as tile thickness increases. An analysis on the failed shots showed that the residual shot weight does not follow a single linear relationship with ceramic tile thickness unlike the residual DoP for all thicknesses of tiles. Post-ballistic analysis on ceramic powder for particle size distribution was carried out and the results are presented.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.477-483, DOI:http://dx.doi.org/10.14429/dsj.64.6745

  17. Q235钢板对平头弹抗侵彻特性研究%Ballistic performance of Q235 metal plates subjected to impact by blunt-nosed projectiles

    Institute of Scientific and Technical Information of China (English)

    邓云飞; 张伟; 孟凡柱

    2015-01-01

    In order to investigate the influence of configuration of target on the ballistic performance, monolithic and three⁃layered targets were normally impacted by blunt⁃nosed projectiles in the velocity range of 190~450 m/s with the help of a gas gun, and also the photos of the impact process were obtained. Based on the tests, the residual velocity versus the initial velocity curves of the projectiles were constructed, and also ballistic limit velocities were obtained. The influence of combination configuration of target on the ballistic characteristic, including the ballistic resistance and failure models were investigated. Moreover, the penetration process of metal plates impacted by rod projectiles had been studied with numerical simulation code ABAQUS/EXPLICIT, and also the validation of models and parameters of materials had been proved by comparing the experiment results with numerical simulations. The results indicated that the ballistic limit velocity of multi⁃layered target was higher than that of monolithic target, and also there were differences between failure models of multi⁃layered targets and monolithic target. Moreover, the failure models of plates of multi⁃layered targets were in relation to their order.%为分析靶体结构对其抗侵彻特性的影响,利用轻气炮进行平头杆弹正撞击单层板和等厚接触式三层板的实验,获取相关的撞击过程图片.通过撞击实验,得到这两种结构靶体的初始-剩余速度曲线以及弹道极限,撞击速度为190~450 m/s.研究靶体结构对抗侵彻特性的影响,包括靶板的失效模式和抗侵彻性能.最后,采用ABAQUS/EXPLICIT软件对杆弹撞击金属板的过程进行数值模拟研究,通过对比数值模拟和实验结果,验证了数值模拟材料模型和参数的有效性.结果表明:多层板的弹道极限高于等厚单层板,并且多层板和单层板的主要失效模式之间存在差异.对于多层板

  18. Ballistic penetration test results for Ductal and ultra-high performance concrete samples.

    Energy Technology Data Exchange (ETDEWEB)

    Reinhart, William Dodd; Thornhill, Tom Finley, III (KTech)

    2010-03-01

    This document provides detailed test results of ballistic impact experiments performed on several types of high performance concrete. These tests were performed at the Sandia National Laboratories Shock Thermodynamic Applied Research Facility using a 50 caliber powder gun to study penetration resistance of concrete samples. This document provides test results for ballistic impact experiments performed on two types of concrete samples, (1) Ductal{reg_sign} concrete is a fiber reinforced high performance concrete patented by Lafarge Group and (2) ultra-high performance concrete (UHPC) produced in-house by DoD. These tests were performed as part of a research demonstration project overseen by USACE and ERDC, at the Sandia National Laboratories Shock Thermodynamic Applied Research (STAR) facility. Ballistic penetration tests were performed on a single stage research powder gun of 50 caliber bore using a full metal jacket M33 ball projectile with a nominal velocity of 914 m/s (3000 ft/s). Testing was observed by Beverly DiPaolo from ERDC-GSL. In all, 31 tests were performed to achieve the test objectives which were: (1) recovery of concrete test specimens for post mortem analysis and characterization at outside labs, (2) measurement of projectile impact velocity and post-penetration residual velocity from electronic and radiographic techniques and, (3) high-speed photography of the projectile prior to impact, impact and exit of the rear surface of the concrete construct, and (4) summarize the results.

  19. One testing method of dynamic linearity of an accelerometer

    Science.gov (United States)

    Lei, Jing-Yu; Guo, Wei-Guo; Tan, Xue-Ming; Shi, Yun-Bo

    2015-09-01

    To effectively test dynamic linearity of an accelerometer over a wide rang of 104 g to about 20 × 104g, one published patent technology is first experimentally verified and analysed, and its deficient is presented, then based on stress wave propagation theory on the thin long bar, the relation between the strain signal and the corresponding acceleration signal is obtained, one special link of two coaxial projectile is developed. These two coaxial metal cylinders (inner cylinder and circular tube) are used as projectiles, to prevent their mutual slip inside the gun barrel during movement, the one end of two projectiles is always fastened by small screws. Ti6-AL4-V bar with diameter of 30 mm is used to propagate loading stress pulse. The resultant compression wave can be measured by the strain gauges on the bar, and a half -sine strain pulse is obtained. The measuring accelerometer is attached on the other end of the bar by a vacuum clamp. In this clamp, the accelerometer only bear compression wave, the reflected tension pulse make the accelerometer off the bar. Using this system, dynamic linearity measurement of accelerometer can be easily tested in wider range of acceleration values. And a really measuring results are presented.

  20. Relativistic electron- and proton-impact ionization of highly stripped heavy ions determined from projectile-electron loss in H2 and He

    International Nuclear Information System (INIS)

    We show that electron- and proton-impact ionization cross sections for highly stripped heavy ions can be deduced from the projectile-electron-loss cross sections determined by collisions with a H2 and a He target. We measure electron loss for 100- and 380-MeV/u Au52+, and 405-MeV/u U86+ in H2 and He targets, and extract the electron- and proton-impact ionization cross sections. Our results are compared with calculations and with channeling experiments

  1. Fission of spin-aligned projectile-like nuclei in the interactions of 29 MeV/nucleon 208Pb with 197Au

    International Nuclear Information System (INIS)

    Binary fission of projectile-like nuclei was investigated in the interaction of 29 MeV/nucleon Pb on Au, together with the associated neutron multiplicity. Fission is only observed in rather peripheral collisions and represents approximately 20% of the total reaction cross-section. The fission process occurs after collisions in which up to 550 MeV have been dissipated. The angular and energy distribution of the fragments can be accounted for by assuming a noticeable spin alignment of the fissioning nuclei. (author) 18 refs.; 3 figs

  2. Direct mass measurements of neutron-rich $^{86}$Kr projectile fragments and the persistence of neutron magic number $N$ = 32 in Sc isotopes

    OpenAIRE

    Xu, Xing; Wang, Meng; Zhang, Yu-Hu; Xu, Hu-Shan; Shuai, Peng; Tu, Xiao-Lin; Litvinov, Yuri A.; Zhou, Xiao-Hong; Sun, Bao-hua; Yuan, You-Jin; Xia, Jia-wen; Yang, Jian-Cheng; Blaum, Klaus; Chen, Rui-jiu; Chen, Xiang-cheng

    2016-01-01

    In this paper, we present direct mass measurements of neutron-rich $^{86}$Kr projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of $^{52-54}$Sc nuclides are determined to be -40492(82), -38928(114), -34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, $^{53}$Sc and $^{54}$Sc are more bound b...

  3. Impact Testing and Analysis of Composites for Aircraft Engine Fan Cases

    Science.gov (United States)

    Roberts, Gary D.; Revilock, Duane M.; Binienda, Wieslaw K.; Nie, Walter Z.; Mackenzie, S. Ben; Todd, Kevin B.

    2002-01-01

    The fan case in a jet engine is a heavy structure because of its size and because of the requirement that it contain a blade released during engine operation. Composite materials offer the potential for reducing the weight of the case. Efficient design, test, and analysis methods are needed to efficiently evaluate the large number of potential composite materials and design concepts. The type of damage expected in a composite case under blade-out conditions was evaluated using a subscale test in which a glass/epoxy composite half-ring target was impacted with a wedge-shaped titanium projectile. Fiber shearing occurred near points of contact between the projectile and target. Delamination and tearing occurred on a larger scale. These damage modes were reproduced in a simpler test in which flat glass/epoxy composites were impacted with a blunt cylindrical projectile. A surface layer of ceramic eliminated fiber shear fracture but did not reduce delamination. Tests on 3D woven carbon/epoxy composites indicated that transverse reinforcement is effective in reducing delamination. A 91 cm (36 in.) diameter full-ring sub-component was proposed for larger scale testing of these and other composite concepts. Explicit, transient, finite element analyses indicated that a full-ring test is needed to simulate complete impact dynamics, but simpler tests using smaller ring sections are adequate when evaluation of initial impact damage is the primary concern.

  4. FAA Development of Reliable Modeling Methodologies for Fan Blade Out Containment Analysis. Part 2; Ballistic Impact Testing

    Science.gov (United States)

    Revilock, Duane M.; Pereira, J. Michael

    2008-01-01

    This report summarizes the ballistic impact testing that was conducted to provide validation data for the development of numerical models of blade out events in fabric containment systems. The ballistic impact response of two different fiber materials - Kevlar 49 (E.I. DuPont Nemours and Company) and Zylon AS (Toyobo Co., Ltd.) was studied by firing metal projectiles into dry woven fabric specimens using a gas gun. The shape, mass, orientation and velocity of the projectile were varied and recorded. In most cases the tests were designed such that the projectile would perforate the specimen, allowing measurement of the energy absorbed by the fabric. The results for both Zylon and Kevlar presented here represent a useful set of data for the purposes of establishing and validating numerical models for predicting the response of fabrics under conditions simulating those of a jet engine blade release situations. In addition some useful empirical observations were made regarding the effects of projectile orientation and the relative performance of the different materials.

  5. Nano-biolistics: a method of biolistic transfection of cells and tissues using a gene gun with novel nanometer-sized projectiles

    Directory of Open Access Journals (Sweden)

    Lummis Sarah CR

    2011-06-01

    Full Text Available Abstract Background Biolistic transfection is proving an increasingly popular method of incorporating DNA or RNA into cells that are difficult to transfect using traditional methods. The technique routinely uses 'microparticles', which are ~1 μm diameter projectiles, fired into tissues using pressurised gas. These microparticles are efficient at delivering DNA into cells, but cannot efficiently transfect small cells and may cause significant tissue damage, thus limiting their potential usefulness. Here we describe the use of 40 nm diameter projectiles - nanoparticles - in biolistic transfections to determine if they are a suitable alternative to microparticles. Results Examination of transfection efficiencies in HEK293 cells, using a range of conditions including different DNA concentrations and different preparation procedures, reveals similar behaviour of microparticles and nanoparticles. The use of nanoparticles, however, resulted in ~30% fewer damaged HEK293 cells following transfection. Biolistic transfection of mouse ear tissue revealed similar depth penetration for the two types of particles, and also showed that 20% in microparticle-transfected samples. Visualising details of small cellular structures was also considerably enhanced when using nanoparticles. Conclusions We conclude that nanoparticles are as efficient for biolistic transfection as microparticles, and are more appropriate for use in small cells, when examining cellular structures and/or where tissue damage is a problem.

  6. Decay analysis of pre-actinide and trans-actinide nuclei formed using various projectiles on a 197Au target at ECN*=60 MeV

    Science.gov (United States)

    Grover, Neha; Kaur, Gurvinder; Sharma, Manoj K.

    2016-01-01

    The collective clusterization approach of the dynamical cluster decay model (DCM) has been applied to study the decay of odd mass nuclei 223Pa*, 215Fr*, 227Np*, and 233Am*, which are formed in heavy-ion-induced reactions. The aim of this study is to investigate the decay pattern and related behavior of these heavy mass nuclei formed in four distinct reactions involving different projectiles (with mass A =18 -36 ) induced on 197Au target nucleus. Further, in order to analyze the role of deformations, the calculations have been done by considering spherical choice of fragmentation as well as with inclusion of quadrupole (β2) deformation. For the heavy mass region, with fission being the dominant decay mode, an attempt has been made to investigate the effect of projectile mass in reference to fission decay patterns of the pre-actinide 215Fr* nucleus and the trans-actinide nuclei 227Np* 223Pa*, 223Am* and formed at common excitation energy, ECN*=60 MeV . Besides this, the shell closure effects and the role of orientation have been explored, which suggest the presence of a noncompound nucleus process such as quasifission (QF) for the odd mass nuclei under consideration. For both the compound nucleus and the noncompound nucleus processes, the results obtained using DCM are found to have nice agreement with experimental observations. The isotopic and isobaric analysis is also worked out so as to have a comprehensive idea about the dynamics involved.

  7. SSNTD studies of lead nuclei fission induced by relativistic p, d, He and sup 1 sup 2 C projectiles inside massive Pb and U targets

    CERN Document Server

    Perelygin, V P; Krivopustov, M I; Petrova, R I; Abdullaev, I G; Bradnova, V; Knjazeva, G P; Brandt, R; Ochs, M; Wan, J S; Vater, P

    1999-01-01

    A series of experiments was carried out with relativistic protons, deuterons, helium and carbon-12 projectiles accelerated at SYNCHOPHASOTRON LHE, Dubna which hit massive Pb and U targets. The beam profiles and intensities of both primary particles and secondary fast neutrons were measured using plastic SSNTD inside the massive cylinder blocks of Cu, Pb and U by counting of fission fragment tracks due to the induced fission of Pb nuclei. The beam diameter increases typically by 20-30% at the depth 10 and 20 cm. With increasing the energy of projectiles the number of secondary neutrons rises with the depth for protons, deuterons and helium ions. Nevertheless, for sup 1 sup 2 C ions beams with changing the energy from 18 GeV to 44 GeV we first observe the effect of significant increase both the yield of secondary fast neutrons and the half-width of the beam. The observed enhanced yield of secondary fast neutrons confirms unusual behavior of nuclear interaction cross section of 44 GeV sup 1 sup 2 C ions observed...

  8. Muerte por proyectil de arma de fuego con orificio de entrada natural Death caused by a projectile gun with a natural entrance hole

    Directory of Open Access Journals (Sweden)

    F. Sánchez

    2010-09-01

    Full Text Available Un proyectil de arma de fuego puede penetrar en el organismo por cualquier parte, originando una lesión cuya morfología puede ser muy variada en función de múltiples factores. No obstante, en ocasiones el lugar de entrada del proyectil puede coincidir con un orificio natural del cuerpo, por lo que la lesión externa no existe. Presentamos un caso de muerte por un único proyectil de arma de fuego cuyo lugar de penetración es uno de los orificios nasales, con la particularidad de que la bala quedó alojada en el interior del cuerpo, no existiendo por tanto lesión de salida. En estas circunstancias se hacen indispensables las técnicas radiológicas como paso previo a la autopsia.A firearm projectile can penetrate through any place of the body, causing injuries whose morphology can be different depending on several factors. However, sometimes the shotgun entrance hole coincides with a body orifice, so the entrance wound could not exist. The authors present a case of a death caused by a single firearm projectile which penetrated through one of the nostrils. The bullet was lodged inside of the body without an exit wound. In those circumstances the radiological techniques are indispensable before to perform the autopsy.

  9. Production of projectile and target K-vacancy in near-symmetric collisions of 60-100 MeV Cu9+ ions with thin Zn target

    Science.gov (United States)

    Yipan, Guo; Zhihu, Yang; Shubin, Du; Hongwei, Chang; Qingliang, Xia; Qiumei, Xu

    2016-03-01

    We report studies on both target and projectile K-shell ionization by collisions of Cu9+ ions on the thin Zn target in the energy range of 60-100 MeV. In this work, the relative ratio for the production of the target to projectile K-vacancy is measured. The result shows that it almost remains stable over this energy range and has good consistency with the predictions by vacancy transfer via the 2pσ-1sσ rotational coupling, which gives experimental evidence for K-vacancy sharing between two partners. Furthermore, the discussion for comparisons between the experimental ionization cross sections and the possible theoretical estimations is presented. These comparisons suggest that the experimental data agree well with those predicted by the Binary-Encounter approximation (BEA) model but are not in good agreement with the modified BEA calculations. It allows us to infer that the direct ionization (and/or excitation) is of importance to initial K-vacancy production before 2pσ-1sσ transitions in the present collision condition. Project supported by the Joint Funds of the National Natural Science Foundation of China (Grant No. U1332122).

  10. Decay analysis of compound nuclei with mass A$\\sim 30-200$ formed in the reactions involving loosely bound projectiles

    CERN Document Server

    Kaur, Mandeep; Sharma, Manoj K; Gupta, Raj K

    2015-01-01

    The dynamics of the reactions forming compound nuclei using loosely bound projectiles is analysed within the framework of dynamical cluster decay model (DCM) of Gupta and Collaborators. We have analysed different reactions with $^{7}Li$, $^{9}Be$ and $^{7}Be$ as neutron rich and neutron deficient projectiles, respectively, on different targets at the three $E_{lab}$ values, forming compound nuclei within the mass region A$\\sim 30-200$. The contributions of light particles LPs ($A\\le4$) cross sections $\\sigma_{LP}$, energetically favoured intermediate mass fragments IMFs ($5 \\le A_2 \\le 20$) cross sections $\\sigma_{IMF}$ as well as fusion-fission $\\it{ff}$ cross sections $\\sigma_{ff}$ constitute the $\\sigma_{fus}$ (=$\\sigma_{LP}$+$\\sigma_{IMF}$+$\\sigma_{ff}$) for these reactions. The contribution of the emitted LPs, IMFs and ff fragments is added for all the angular momentum upto the $\\ell_{max}$ value, for the resepctive reactions. Interestingly, we find that the $\\Delta R^{emp}$, the only parameter of model ...

  11. A novel facility for reduced-gravity testing: A setup for studying low-velocity collisions into granular surfaces.

    Science.gov (United States)

    Sunday, C; Murdoch, N; Cherrier, O; Morales Serrano, S; Valeria Nardi, C; Janin, T; Avila Martinez, I; Gourinat, Y; Mimoun, D

    2016-08-01

    This work presents an experimental design for studying low-velocity collisions into granular surfaces in low-gravity. In the experiment apparatus, reduced-gravity is simulated by releasing a free-falling projectile into a surface container with a downward acceleration less than that of Earth's gravity. The acceleration of the surface is controlled through the use of an Atwood machine, or a system of pulleys and counterweights. The starting height of the surface container and the initial separation distance between the projectile and surface are variable and chosen to accommodate collision velocities up to 20 cm/s and effective accelerations of ∼0.1 to 1.0 m/s(2). Accelerometers, placed on the surface container and inside the projectile, provide acceleration data, while high-speed cameras capture the collision and act as secondary data sources. The experiment is built into an existing 5.5 m drop tower frame and requires the custom design of all components, including the projectile, surface sample container, release mechanism, and deceleration system. Data from calibration tests verify the efficiency of the experiment's deceleration system and provide a quantitative understanding of the performance of the Atwood system. PMID:27587140

  12. A novel facility for reduced-gravity testing: A setup for studying low-velocity collisions into granular surfaces

    Science.gov (United States)

    Sunday, C.; Murdoch, N.; Cherrier, O.; Morales Serrano, S.; Valeria Nardi, C.; Janin, T.; Avila Martinez, I.; Gourinat, Y.; Mimoun, D.

    2016-08-01

    This work presents an experimental design for studying low-velocity collisions into granular surfaces in low-gravity. In the experiment apparatus, reduced-gravity is simulated by releasing a free-falling projectile into a surface container with a downward acceleration less than that of Earth's gravity. The acceleration of the surface is controlled through the use of an Atwood machine, or a system of pulleys and counterweights. The starting height of the surface container and the initial separation distance between the projectile and surface are variable and chosen to accommodate collision velocities up to 20 cm/s and effective accelerations of ˜0.1 to 1.0 m/s2. Accelerometers, placed on the surface container and inside the projectile, provide acceleration data, while high-speed cameras capture the collision and act as secondary data sources. The experiment is built into an existing 5.5 m drop tower frame and requires the custom design of all components, including the projectile, surface sample container, release mechanism, and deceleration system. Data from calibration tests verify the efficiency of the experiment's deceleration system and provide a quantitative understanding of the performance of the Atwood system.

  13. Study on measurement method of the projectiles velocity and target coordinates of twin-tube volleyed weapons%双管齐射武器弹丸速度和着靶坐标测试方法研究

    Institute of Scientific and Technical Information of China (English)

    邹剑军; 王文博; 宋玉贵; 王国珲

    2011-01-01

    为了解决靶场测试中对于双管齐射武器飞行矢量和着靶坐标的测量问题,提高测试精度,介绍了一种基于多幕面装置的非接触测试方法.文中详细介绍了装置的构成,分析了测试方法的原理,并利用MatLab软件进行了仿真测试,根据其技术特点和仿真结果,对工程应用存在的实际问题进行了讨论.装置系统可以完成对双管齐射武器的测试,能够区分弹丸穿过幕面的正确时序并根据相应规则进行计算并得出结果.%A multi-screen structure of non-contacted method was presented to solve the measurement of the projectiles velocity and position of twin-tube volleyed weapons and to enhance the precision. The principle of the method and the device composition are explained in detail, and according to the MatLab to carry out simulation testing, discussing the practical problem based on engineering application. The device can differentiate the true moment of the twin-tube volleyed weapons when they are crossing the sky screen and the result will be obtained in terms of corresponding rules.

  14. Effect of armature material and projectile pullback weight to ship-borne coilgun efficiency%电枢材料和弹丸配重对舰载线圈炮效率的影响

    Institute of Scientific and Technical Information of China (English)

    陈学慧; 曹延杰; 王成学; 王慧锦

    2013-01-01

    针对工程中常用的电枢材料,通过改变弹丸配重,寻找各配重情况下电枢的最佳初始位置,应用数值仿真对舰载线圈炮的能量转换效率进行研究,得到电枢材料和弹丸配重对能量转换效率的影响规律.结果表明,对于一个特定的舰载线圈炮系统,存在一个最佳的弹丸配重使有效载荷的能量转换效率达到最大,为舰载线圈炮的电枢和弹丸设计提供参考.%Take projectile pullback weight as variable,the energy conversion efficiency of ship-borne coilgun is analyzed applying numerical simulation through searching the respective optimal initial location to materials which is common used in engineering.The research result indicates that there existed an optimal pullback weight for a definite ship-borne coilgun system ; the law of the effect on projectile pullback weight to projectile and payload efficiency is obtained through optimize the respective armature initial location,which provides the theoretical reference for design of the armature and projectile.

  15. Projectile charge state dependence of M-shell ionization of Au, Pb, Bi, and U by 1.42-MeV/amu fluorine ions

    International Nuclear Information System (INIS)

    The present study was undertaken to determine the direct ionization and electron capture contributions to vacancy production in the M-shells of 79Au, 82Pb, 83Bi and 92U for incident 199F ions. M-shell x-ray production cross sections have been measured for 1.42-MeV/amu 199Fq+ ions for q = 4,5,6,8,9. Enhancements in the target x-ray production cross sections were observed for projectiles with one and two K-shell vacancies over those without K-shell vacancies. Direct ionization and electron capture contributions to the vacancy production were extracted from the data and compared to the plane wave Born approximation and to the Oppenheimer-Brinkman-Kramers calculations of Nikolaev, respectively

  16. Filtre à fenêtre glissante pour l'estimation de l'attitude et des vitesses d'un projectile

    OpenAIRE

    Grandvallet, Bertrand; Zemouche, Ali; Boutayeb, Mohamed; Changey, Sébastien

    2010-01-01

    National audience Ce papier traite du problème de guidage d'un projectile stabilisé par rotation. Nous apportons une contribution au niveau la navigation grâce à des capteurs ”bas-coût” de type accéléromètres et magnétomètres. Les fortes non-linéarités présentes dans les équations d'états (dynamique et sortie) du modèle nous restreignent à l'utilisation de peu de méthodes d'estimation. Nous proposons ici un Filtre de Kalman Etendu (FKE) utilisant une fenêtre glissante sur les mesures pour ...

  17. Sputtering of tungsten: an atomic view of a near-surface depleted zone created by a single 30 keV 63Cu+ projectile. Report No. 4118

    International Nuclear Information System (INIS)

    The vacancy structure of a near-surface depleted zone (DZ), created by a single 30 keV 63Cu+ ion in a tungsten field-ion microscope (FIM) specimen, was determined with atomic resolution. Both the irradiation and pulse field-evaporation experiments were performed in situ at less than or equal to 11 K, so that the observed vacancy structure was unaltered by the long-range migration of self-interstitial atoms. The following basic physical quantities were measured: (1) the number of vacancies; (2) the dimensions; (3) the vacancy concentration; (4) the distribution of first-nearest-neighbor vacancy clusters; and (5) the radial-distribution function for the vacancies out to ninth-nearest neighbor. The values of these quantities were shown to be similar for both the near-surface DZ and DZs created in the bulk of the same specimen by 30 keV 63Cu+ projectiles

  18. Theoretical study of projectile fragmentation in the reactions $^{112}$Sn + $^{112}$Sn and $^{124}$Sn + $^{124}$Sn at 1 GeV/nucleon

    CERN Document Server

    Imal, H; Buyukcizmeci, N; Ogul, R; Botvina, A S; Trautmann, W

    2014-01-01

    We analyze the production cross sections and isotopic distributions of projectile-like residues in the reactions $^{112}$Sn + $^{112}$Sn and $^{124}$Sn + $^{124}$Sn at an incident beam energy of 1 GeV/nucleon measured with the FRS fragment separator at the GSI laboratory. Calculations within the statistical multifragmentation model (SMM) for an ensemble of excited sources were performed with ensemble parameters determined previously for similar reactions at 600 MeV/nucleon. The obtained good agreement with the experiment establishes the universal properties of the excited spectator systems produced during the dynamical stage of the reaction. It is furthermore confirmed that a significant reduction of the symmetry-energy term at the freeze-out stage of reduced density and high temperature is necessary to reproduce the experimental isotope distributions. A trend of decreasing symmetry energy for large neutron-rich fragments of low excitation energy is interpreted as a nuclear-structure effect.

  19. Direct mass measurements of neutron-rich 86Kr projectile fragments and the persistence of neutron magic number N=32 in Sc isotopes

    Science.gov (United States)

    Xu, Xing; Wang, Meng; Zhang, Yu-Hu; Xu, Hu-Shan; Shuai, Peng; Tu, Xiao-Lin; Yuri, A. Litvinov; Zhou, Xiao-Hong; Sun, Bao-Hua; Yuan, You-Jin; Xia, Jia-Wen; Yang, Jian-Cheng; Klaus, Blaum; Chen, Rui-Jiu; Chen, Xiang-Cheng; Fu, Chao-Yi; Ge, Zhuang; Hu, Zheng-Guo; Huang, Wen-Jia; Liu, Da-Wei; Lam, Yi-Hua; Ma, Xin-Wen; Mao, Rui-Shi; Uesaka, T.; Xiao, Guo-Qing; Xing, Yuan-Ming; Yamaguchi, T.; Yamaguchi, Y.; Zeng, Qi; Yan, Xin-Liang; Zhao, Hong-Wei; Zhao, Tie-Cheng; Zhang, Wei; Zhan, Wen-Long

    2015-10-01

    In this paper, we present direct mass measurements of neutron-rich 86Kr projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of 52-54Sc nuclides are determined to be -40492(82), -38928(114), -34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, 53Sc and 54Sc are more bound by 0.8 MeV and 1.0 MeV, respectively. The behavior of the two neutron separation energy with neutron numbers indicates a strong sub-shell closure at neutron number N=32 in Sc isotopes. Supported by 973 Program of China (2013CB834401), the NSFC (U1232208, U1432125, 11205205, 11035007) and the Helmholtz-CAS Joint Research Group (HCJRG-108)

  20. Generation of ultra-high-pressure shocks by collision of a fast plasma projectile driven in the laser-induced cavity pressure acceleration scheme with a solid target

    Energy Technology Data Exchange (ETDEWEB)

    Badziak, J.; Rosiński, M. [Institute of Plasma Physics and Laser Microfusion, 01-497 Warsaw (Poland); Krousky, E. [Institute of Physics AS CR, 182 21 Prague 8 (Czech Republic); Kucharik, M.; Liska, R. [Czech Technical University, FNSPE, 160 41 Prague 6 (Czech Republic); Ullschmied, J. [Institute of Plasma Physics AS CR, 182 20 Prague 8 (Czech Republic)

    2015-03-15

    A novel, efficient method of generating ultra-high-pressure shocks is proposed and investigated. In this method, the shock is generated by collision of a fast plasma projectile (a macro-particle) driven by laser-induced cavity pressure acceleration (LICPA) with a solid target placed at the LICPA accelerator channel exit. Using the measurements performed at the kilojoule PALS laser facility and two-dimensional hydrodynamic simulations, it is shown that the shock pressure ∼ Gbar can be produced with this method at the laser driver energy of only a few hundred joules, by an order of magnitude lower than the energy needed for production of such pressure with other laser-based methods known so far.

  1. NA49 event display of the reconstructed tracks emanating from the "little bang" created in a central collision of Lead projectile with a Lead nucleus

    CERN Multimedia

    1996-01-01

    When a 33 TeV Lead nucleous projectile hits head on a Lead target it creates for a brief instant of time a system of quarks and gluons that more than 100'000 times hotter than the sun. As this fireball expands it reconstitutes normal matter creating thousands of particles (pions, kaons, protons, ....). The NA49 Time Projection Chambers extending over 13 m can record a large majority of the produced charged particles. The result of a complex analysis is shown here in a event display of the reconstructed tracks. The blue lines represent the boundaries of the detectors in a perspective view from the far end of the experiment towards the interaction point, where all the tracks originate.

  2. Direct mass measurements of neutron-rich $^{86}$Kr projectile fragments and the persistence of neutron magic number $N$ = 32 in Sc isotopes

    CERN Document Server

    Xu, Xing; Zhang, Yu-hu; Xu, Hu-shan; Shuai, Peng; Tu, Xiao-lin; Litvinov, Yuri A; Zhou, Xiao-hong; Sun, Bao-hua; Yuan, You-jin; Xia, Jia-wen; Yang, Jian-cheng; Blaum, KLaus; Chen, Rui-jiu; Chen, Xiang-cheng; Fu, Chao-yi; Ge, Zhuang; Hu, Zheng-guo; Huang, Wen-jia; Liu, Da-wei; Lam, Yi-hua; Ma, Xin-wen; Mao, Rui-shi; Uesaka, T; Xiao, Guo-ging; Xing, Yuan-ming; Yamaguchi, T; Yamaguchi, Y; Zeng, Qi; Yan, Xin-liang; Zhao, Hong-wei; Zhao, Tie-cheneg; Zhang, Wei; Zhan, Wen-long

    2016-01-01

    In this paper, we present direct mass measurements of neutron-rich $^{86}$Kr projectile fragments conducted at the HIRFL-CSR facility in Lanzhou by employing the Isochronous Mass Spectrometry (IMS) method. The new mass excesses of $^{52-54}$Sc nuclides are determined to be -40492(82), -38928(114), -34654(540) keV, which show a significant increase of binding energy compared to the reported ones in the Atomic Mass Evaluation 2012 (AME12). In particular, $^{53}$Sc and $^{54}$Sc are more bound by 0.8 MeV and 1.0 MeV, respectively. The behavior of the two neutron separation energy with neutron numbers indicates a strong sub-shell closure at neutron number $N$ = 32 in Sc isotopes.

  3. Questions for Parents to Ask about School Adaptations. PHP-c91

    Science.gov (United States)

    PACER Center, 2004

    2004-01-01

    A child with a disability who has an Individualized Education Program (IEP) or Section 504 Accommodation Plan may need extra help and support to participate in school. It takes thoughtful planning to choose adaptations, based on a child's disability, to help the child learn or have access to learning. Appropriate accommodations vary with…

  4. On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25 mm projectiles

    Directory of Open Access Journals (Sweden)

    John F. Moxnes

    2016-04-01

    Full Text Available We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle exists beyond which ricochet cannot occur. The Autodyn simulation code with the smooth particle hydrodynamic (SPH method and Impetus Afea Solver with the corpuscular model are used and the results are compared with experimental and analytical results. The resistance force in sand for spheres was proportional to a term quadratic in velocity plus a term linear in velocity. The drag coefficient for the quadratic term was 0.65. The Autodyn and Impetus Afea codes simulate too large penetration due to the lack of a linear velocity resistance force. Critical ricochet angles were consistent with analytical results in the literature. In ballistic gelatin at velocities of 50–850 m/s a drag coefficient of 0.30 fits the high speed camera recordings if a linear velocity resistance term is included. However, only a quadratic velocity resistance force with drag coefficient that varies with the Reynolds number also fits the measurements. The simulation of a sphere in water with Autodyn showed too large drag coefficient. The 7.62 mm APM2 core simulations in sand fit reasonable well for both codes. The 25 mm projectile ricochet simulations in sand show consistency with the high speed camera recordings. Computer time was reduced by one to two orders of magnitudes when applying the Impetus Afea Solver compared to Autodyn code due to the use of the graphics processing units (GPU.

  5. On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25 mm projectiles

    Institute of Scientific and Technical Information of China (English)

    John F. MOXNES; Øyvind FRØYLAND; Stian SKRIUDALEN; Anne K. PRYTZ; Jan A. TELAND; Eva FRIIS; Gard ØDEGÅRDSTUEN

    2016-01-01

    We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle) exists beyond which ricochet cannot occur. The Autodyn simulation code with the smooth particle hydrodynamic (SPH) method and Impetus Afea Solver with the corpuscular model are used and the results are compared with experimental and analytical results. The resistance force in sand for spheres was proportional to a term quadratic in velocity plus a term linear in velocity. The drag coefficient for the quadratic term was 0.65. The Autodyn and Impetus Afea codes simulate too large penetration due to the lack of a linear velocity resistance force. Critical ricochet angles were consistent with analytical results in the literature. In ballistic gelatin at velocities of 50–850 m/s a drag coefficient of 0.30 fits the high speed camera recordings if a linear velocity resistance term is included. However, only a quadratic velocity resistance force with drag coefficient that varies with the Reynolds number also fits the measurements. The simulation of a sphere in water with Autodyn showed too large drag coefficient. The 7.62 mm APM2 core simulations in sand fit reasonable well for both codes. The 25 mm projectile ricochet simulations in sand show consistency with the high speed camera recordings. Computer time was reduced by one to two orders of magnitudes when applying the Impetus Afea Solver compared to Autodyn code due to the use of the graphics processing units (GPU).

  6. Quantizing Analysis and Processing of Test Conditions for Infantry Grenade Ignition Characteristics

    Institute of Scientific and Technical Information of China (English)

    SHAN Yong-hai; ZHANG Bing; SUN Guo-ji

    2005-01-01

    A rule of how the ignition probability or invalidation probability of infantry grenade varies with the projectile quantity is presented based on the statistical analysis. The statistical induction, quantizing analysis and data processing in the infantry grenade type approval test are completed, and we obtain how various test factors in the research item affect the test results(invalidation probability), i.e., quantized data. The acquisition of these quantized data provides theory basis and data auspice for further reasonable filtration of all test factors and the optimization of test scheme.

  7. Explicit Finite Element Modeling of Multilayer Composite Fabric for Gas Turbine Engine Containment Systems, Phase II. Part 2; Ballistic Impact Testing

    Science.gov (United States)

    Revilock, D. M.; Pereira, J. M.

    2009-01-01

    This report summarizes the ballistic impact testing that was conducted to provide validation data for the development of numerical models of blade-out events in fabric containment systems. The ballistic impact response of two different fiber materials - Kevlar(TradeName) 49 and Zylon(TradeName) AS (as spun) was studied by firing metal projectiles into dry woven fabric specimens using a gas gun. The shape, mass, orientation, and velocity of the projectile were varied and recorded. In most cases, the tests were designed so the projectile would perforate the specimen, allowing measurement of the energy absorbed by the fabric. The results for both Zylon and Kevlar presented here represent a useful set of data for the purposes of establishing and validating numerical models to predict the response of fabrics under conditions that simulate those of a jet engine blade-release situation. In addition, some useful empirical observations were made regarding the effects of projectile orientation and the relative performance of the different fabric materials.

  8. 弹丸冲击贯穿有限厚混凝土材料靶板的背面成坑效应%Rear face crater-forming of a limited-thickness concrete target due to projectile penetrating

    Institute of Scientific and Technical Information of China (English)

    纪冲; 龙源; 高振儒; 周望远

    2013-01-01

    弹丸冲击贯穿有限厚混凝土靶板后,靶板背面有大块的混凝土剥落,形成近似的锥形坑.为了研究背面弹坑半锥角θ这一作为混凝土靶板贯穿后破坏范围问题研究中的重要参量,将贯穿问题等效为轴对称条件下的冲切破坏问题.采用双剪应力三参数强度准则及刚塑性模型,得到了极限应力圆的包络线方程,给出了轴对称破坏机构,进而求得θ值的表达式.理论计算结果与数值模拟结果、实验数据三者之间吻合度较好.研究表明,θ值由混凝土材料抗压强度与抗拉强度比值决定.基于上述研究,提出在混凝土中掺加钢纤维以提高有限厚靶板抗贯穿能力的实际方法,并进行了弹道实验.实验结果表明,贯穿破坏后靶板碎片的数量及θ大幅降低,显示了高含量异型钢纤维混凝土在抗贯穿方面的适用性.%Tests for projectile penetrating limited-thickness concrete target revealed that concrete chunks spall off from the rear face of the target and a conical crater forms in the process of penetration. The determination of the cone crack angle 0 in a concrete target subjected to a projectile impact is important when assessing the level of the damage in the target. The perforation failure of concrete slab was simplified as a problem of punching. With the twin-shear stress three-parameter strength criterion and a rigid-plastic model, an axial symmetrical failure mechanism was given and the failure envelope of stress circle was found to be two straight lines. Then the expression of 0 was obtained. The study showed that θ is controlled by the ratio of the compressive strength to tensile strength of the concrete material. Based on the above theoretical analysis, the approach to improve and-perforation performances of targets by adding steel-fiber into concrete was proposed. Ballistic experiments were performed by using a φ12.7mm ballistic gun. The experiments showed that the quantity and scattering

  9. 中口径火炮提前发射修正弹反导能力研究%Research on Leading Launching Trajectory Correction Projectile of Medium Caliber Gun Against Missile

    Institute of Scientific and Technical Information of China (English)

    陈红彬; 钱林方

    2012-01-01

    To improve the remote antimissile capability of medium caliber gun (MCG), an antimissile project was put forward by leading launching one-dimensional damping trajectory-correction-projectile (TCP) according to the ballistic characteristics and flight principle. The projectile-target encounter time errors were introduced to antimissile errors and hitting models of MCG. The flight time errors of projectile were gained and corrected by using simulation statistic method. Kill probabilities of TCP and uncorrected projectile against cruise guided missile were simulated in a long range. The resluts show that it can greatly improve antimissile capability of MCG in a long range by increasing damping in terminal trajectory to correct encounter time errors of projectile-target. The results offer reference for antimissile operational use of MCG.%为了提高中口径火炮远距离反导能力,针对一维阻尼环机构弹道修正弹的弹道特性和飞行原理,提出提前发射修正弹用于反导的设想,将弹目交汇时间误差融入到中口径火炮对空误差及命中毁伤模型中,采用仿真统计法,获取并修正每发射弹的飞行时间误差,仿真计算得出修正弹与无控弹远距离对巡航导弹的毁伤概率.结果表明:弹道末端通过增阻减速修正弹目交汇时间误差能够大幅提升中口径火炮的远距离反导能力,研究结果为中口径火炮的反导作战使用提供了参考.

  10. 串联弹前级装药对后级随进弹爆炸作用的研究%Investigation of Explosive Effect to Followed Projectiles by Shaped Charge of Tandem Warhead

    Institute of Scientific and Technical Information of China (English)

    康彦龙; 蒋建伟; 王树有; 门建兵

    2011-01-01

    The explosion of shaped charge of tandem warhead and the impact process on followed projectile of impulse are simulated with a numerical hydrocode of AUTODYN.The maximum acceleration response and kinetic energy attenuation of followed projectile during impact process are analyzed under different projectile mass and diameter.The result indicates that the projectile's maximum acceleration decreased,remainder kinetic energy increased with followed projectile mass increased.An equation of followed projectile's residual velocity with projectile mass is concluded based on simulation results,and it is validated by experimental results.%为获得串联战斗部随进弹在受到前级装药爆炸作用时,质量对其所受最大过载及动能衰减的影响规律,采用非线性动力学软件AUTODYN,基于Euler-Lagrange耦合算法,对前级装药的爆炸过程中,不同弹径、不同质量的随进弹穿越爆轰场进行了数值模拟。得出了随进弹在前级爆炸作用下所受最大过载和动能衰减的变化规律。基于数值模拟结果建立了随进弹剩余速度与质量的无量纲关系式,计算结果得到了实验验证。

  11. 钢筋混凝土靶体抗弹体斜侵彻试验分析%Experimental and analysis on oblique penetration of projectiles into reinforced concrete target

    Institute of Scientific and Technical Information of China (English)

    刘勇; 宋春明; 黄育; 刘斌

    2013-01-01

    To investigate the failure effects of reinforced concrete under oblique penetration and the influences of the reinforcing mat, ballistic experiments with the same oblique angle were performed by use of φ57mm projectile, the impact velocity, penetration depth, crater range and other testing parameters were provided, and the effects of reinforcing steel were also analyzed. The tests show that the destruction of the internal concrete got availably restrained by the reinforcing steel net for its good anti-tensile effect. The available formula for calculating the penetration depth do not reflect the effects of the reinforcing mat, but the reinforcing steel net can be regarded as an equivalent steel plate for its influence of the membrane force, then the penetration depth were obtained according to the method of the layered medium. The calculation results are compared with those of the empirical formula and the test data verify its validity.%为研究斜侵彻钢筋混凝土靶体的破坏特征并分析靶体中钢筋的作用,利用直径57 mm的弹体对3个钢筋混凝土靶体进行相同倾角的斜侵彻试验,得到着靶速度及对应的侵彻深度、弹坑范围等试验参数,结合试验分析了靶体中钢筋的作用.试验表明:钢筋网使内部混凝土的破坏得到有效抑制,整体抗拉作用明显,钢筋网整体作用类似于膜力.将靶体中钢筋网等效为一定厚板的钢板层,按照分层介质计算方法,得出了钢筋混凝土斜侵彻深度计算公式,解决了现有公式不能反映靶体中钢筋作用的不足.计算结果与数值模拟结果及经验公式计算结果进行了比较,吻合较好,验证了其有效性.

  12. Design and testing of a 0. 60 caliber, augmented railgun

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, R.L.; Kitzmiller, J.R.; Ingram, M.W. (Texas Univ., Austin, TX (United States). Center for Electromechanics)

    1991-01-01

    The Center for Electromechanics at The University of Texas at Austin (CEM-UT) is currently in the manufacturing phase of a 29-month program to build and test a laboratory based small caliber electromagnetic (EM) launcher and compulsator power supply. The goal of the EM launcher is to deliver a three shot projectile salvo at 10 Hz. The muzzle energy of each 32-g projectile is 64 kJ, which yields an exit velocity of 2,000 m/s. A full-scale, 0.60 caliber, 1.6 m prototype railgun has been built and is currently being tested at CEM-UT. This augmented railgun incorporates a low mass, high inductance gradient (1.25 {mu}H/m) design. High strength stainless-steel laminations support the primary and augmenting rail package in a compact and inherently stiff design. Rail erosion is minimized by the use of molybdenum for the primary rails. Copper is used for the end turns and augmenting conductors to ensure reliable bolted connections and to reduce the overall gun resistance. The laminations are insulated using epoxy adhesive and held in compression using an overwrapped composite preload tube. The entire gun weighs less than 100 kg and will be mounted to a recoil mechanism when fired from the compulsator power supply. This paper presents the design for the 0.60 caliber augmented, laminated, solid-armature railgun. Included is the discussion of the magnetic pressure distribution and heating on the molybdenum and copper conductors, and gun stiffness as predicted by finite-element analysis. The inductance gradient is calculated and correlated to experimental results. The materials selection, fabrication details, and insulation methods are also discussed. Finally, gun performance is presented through experimental data collected from testing solid armature projectiles.

  13. 刚性弹丸侵彻钢筋混凝土的实验和简化分析模型%Experiment and Simplified Analytical Model for Penetration of Rigid Projectile in a Reinforced Concrete Target

    Institute of Scientific and Technical Information of China (English)

    黄民荣; 顾晓辉; 高永宏

    2009-01-01

    通过Φ57mm半穿甲弹对钢筋混凝土的垂直侵彻实验,得到了弹丸的撞靶速度、成坑深度、最大侵彻深度以及过载时程曲线等实验数据.对实验后钢筋的断裂特征进行分析,得到钢筋的典型破坏模式.将钢筋的破坏简化为弯曲+剪切断裂和弯曲+拉伸断裂这两种模式.根据混凝土侵彻模型和梁断裂失效理论,建立了刚性弹丸垂直侵彻钢筋混凝土的简化分析模型.将理论计算得到的侵彻深度、速度与过载时间历程分别与实验数据进行对比,结果表明两者吻合较好.研究表明,钢筋只对弹体侵彻过程产生局部影响,混凝土的抗侵彻阻力仍是钢筋混凝土抗侵彻阻力的主要组成部分.%Experiments on perpendicular penetration of 57-mm-diameter semi-armor-piercing projectile in a reinforced concrete target were conducted. Striking velocity, impact crater depth, maximum penetration depth and penetration deceleration-time history of projectile were measured. Based on the analysis of rupture characteristics of steel bars subjected to projectile impact, a typical steel bar breakage model was obtained. The steel bars breakage model was simplified as following two models: bending plus shear rupture and bending plus tension rupture. A simplified analytical model for penetration in a reinforced concrete target subjected to rigid projectile impact was developed based on the penetration model for concrete target and the rupture failure theory for a beam. Prediction of penetration depth, velocity and penetration deceleration-time history from this model are in agreement with above-mentioned experimental data. Investigation indicates that the steel bars only contribute local effects on the penetration process. The resistance of concrete materials to penetration of projectile is the main component of resistance to penetration of projectile in a reinforced concrete target.

  14. Ionization and excitation of lithium atoms by fast charged particle impact: identification of mechanisms for double K-shell vacancy production as a function of the projectile charge and velocity; Ionisation et excitation de l'atome de lithium par impact de particules chargees rapides: Identification des mecanismes de creation de deux lacunes en couche K du lithium en fonction de la charge et de la vitesse du projectile

    Energy Technology Data Exchange (ETDEWEB)

    Rangama, J

    2002-11-01

    Ionization and excitation of lithium atoms by fast charged particle impact: identification of mechanisms for double K-shell vacancy production as a function of projectile charge and velocity. Auger electron spectroscopy is used for an experimental investigation of ionization and excitation of lithium atoms by ions (Kr34{sup +} and Ar18{sup +}) and electrons at high impact velocities (from 6 to 60 a.u.). In particular, relative contributions of the mechanisms responsible for lithium K-shell ionization-excitation are determined for various projectile charges Zp and velocities vp. A large range of perturbation parameters |Zp|/vp is explored (|Zp|/vp = 0,05 - 0,7 a.u.). From single K-shell excitation results, it appears that the projectile-electron interaction gives mainly rise to a dipole-like transition 1s -> np Concerning K-shell ionization-excitation, the separation of the TS2 (two independent projectile-electron interactions) and TS1 (one projectile-electron interaction) mechanisms responsible for the formation of the 2snp 1,3P and 2sns 1,3S lithium states is performed. In TS1 process, the projectile-electron interaction can be followed by an electron-electron interaction (dielectronic process) or by an internal rearrangement of the residual target after a sudden potential change (shake process). From Born theory, ab initio calculations are performed. The good agreement between theoretical and experimental results confirms the mechanism identification. For the production of P states, TS1 is found to be strongly dominant for small |Zp|/vp values and TS2 is found to be most important for large |Zp|/vp values. Since P states cannot be formed significantly via a shake process, the TS1 and TS2 separation provides a direct signature of the dielectronic process. On the other hand, the TS1 process is shown to be the unique process for producing the S states. At the moment, only the shake aspect of the TS1 process can explain the fact that the 2s3s configuration is

  15. Model and Research of Melting-wear Between Projectile and Gun Barrel%身管与弹丸的熔融磨损模型与研究

    Institute of Scientific and Technical Information of China (English)

    梁文凯; 周克栋; 李践飞

    2015-01-01

    针对身管的烧蚀磨损会制约武器的进一步发展的问题,提出一种身管与弹丸的熔融磨损的计算方法。通过分析管与弹丸发生熔融磨损过程,将摩擦学和流体力学相关理论运用到身管与弹丸的高温、高速摩擦作用中,建立了身管与弹丸的熔融磨损模型,推导出了熔融润滑状态下的熔化液熔化速度、熔化液厚度及摩擦系数的计算公式,并以某加农炮为例对所建模型进行理论计算与分析。计算结果表明:该方法较好地符合了现有的摩擦学理论,为深入研究身管武器的烧蚀磨损机理提供了理论基础。%Aiming at the problem of erosion and wear of gun barrels will restrict the weapon’s further developments, proposes a method for calculating melting-wear of the projectile and gun barrel. By analyzing the process of the melting-wear, use the tribology and hydromechanics theory, the melting-wear model of the interaction with high temperature and high speed between projectile and gun barrel was established and the related parameters of melting speed and thickness of melted liquid and the friction coefficient were derived. With cannon as an example, the theoretical calculations and analyses were conducted based on the established model. The obtained results were in good agreement with the current tribology theory. The melting-wear model in this paper can provide theoretical references for further studies of the erosion and wear mechanism of gun barrels.

  16. 陀螺转子随载体的进动对末制导炮弹弹道影响%Influence of Gyroscopic Precession on Ballistic of Terminal Guided Projectile

    Institute of Scientific and Technical Information of China (English)

    佟德飞; 宋卫东; 杨晓霖

    2014-01-01

    The ballistic of a model certain terminal guided projectile was built and considered as a system made up with body and inertial gyro, for analyzed the influence of precession inertial gyro on ballistic, but the dynamic of body transferred to gyro was neglected. To study directional characteristic of rotor, the moment of external frame and internal frame transferred from carrier were calculated. The simulation software for terminal guided projectile was compiled, and the numerical simulation of extended-range trajectory was carried out. The conclusions suggest that the influence gyroscopic precession on ballistic characteristics of terminal guided projectile can be ignored, it has important instructive significance to design new type of terminal guided projectile.%以往将末制导炮弹视为由弹体以及惯导陀螺组成的两刚体系统,以分析陀螺动力学特性对弹体弹道特性的影响,而忽略弹体运动对惯导陀螺转子定向性的作用。为了确定惯导陀螺转子定向性对弹道特性产生的影响,通过计算运载体传递到内、外框架的作用力矩,得到陀螺转子进动角速度模型,对末制导炮弹惯导飞行增程段弹道进行仿真,分析得到转子在空间的运动并非具有定轴性,而是会产生一定的偏转,且陀螺转子进动对弹道特性产生一定影响的结论。

  17. Research on the Method of Measuring Projectiles Attitude Angle by Magnetometer%基于地磁传感器的弹体姿态角测量方法研究

    Institute of Scientific and Technical Information of China (English)

    邱荣剑; 宓卉

    2012-01-01

    Along with many country attaching important to the informationization of ammunition, the technology of measuring projectile attitude angle by geomagnetic sensor has been developed fast. Now,domestic equipment of measuring projectile attitude angle by geomagnetic sensor only can measure the roll angle and roll rates. In this paper, a method of measure projectiles attitude angle by a tri-axial vector magne- tometer has been introduced. In this method, the vector magnetometer first measures the magnetic field intensity and its change rate, then uses this data to calculate projectiles attitude angle. The efSectiveness of this method is only dependent on the accuracy of the vector magnetome- ter, so this method has high value of engineering application.%随着各国对信息化弹药的重视,地磁传感器测姿技术也得到快速发展。目前国内的地磁测姿设备仅能测量弹体的滚转角及转速,文章介绍了一种利用三轴矢量磁力计测量飞行弹体在弹体坐标系下的磁场强度及磁场强度变化率,然后通过测得的磁场强度及变化率求解弹体姿态(俯仰角、偏航角及滚转角)的理论计算方法,该测量方法的精度主要取决于矢量磁力计的测量精度,具有很高的工程应用价值。

  18. Yield of isomers in 76Ge (635 MeV) + 198Pt deep-inelastic collision and their dependence on projectiles (74,76Ge) and beam energies (635,550 MeV)

    International Nuclear Information System (INIS)

    We report the yields and distribution of ns-μs isomers produced in 76Ge (635 MeV) + 198Pt deep-inelastic collision. The population yields of isomers evaluated for individual channel and compared with the relevant yields produced in 76Ge (635 MeV) + 198Pt and 74Ge (550 MeV) + 198Pt reaction. These comparisons reflect how isomer yield depends on beam energies and projectile mass in deep-inelastic collisions. (author)

  19. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    OpenAIRE

    Magier M.; Kruszka L.

    2012-01-01

    The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity) in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with ...

  20. Time-of-flight mass spectrometry with desorption-ionization multiprobes (UV photons and KeV and MeV particles). Cluster atoms are used as projectiles

    International Nuclear Information System (INIS)

    A new time-of-flight mass spectrometer, Super-Depil, is used to study secondary ion emission from solid surfaces bombarded by various kinds of primary particles. Three different desorption probes were set up on this machine: a 252 californium source, providing by spontaneous fission about 1 MeV/u energy heavy ions, a 5 to 30 keV energy pulsed caesium ion gun and a pulsed nitrogen laser, which wavelength is 337 mm. A two stages electrostatic mirror was added to the spectrometer. The time spread due to the initial kinetic energy of secondary ions leaving the surface was minimized. The mass resolution is greater than 5000. The analysis of glycosidic terpenes showed the complementarity of the three probes. The study of such metastable ions, with the electrostatic mirror, showed that some fragment ions may conserve the memory of the stereochemistry of the neutral lost. Clusters ions were used as projectiles in the energy range 5-60 keV. A strong non linear enhancement was observed in the secondary ion yield from various targets

  1. Multiplicity of secondary electrons emitted by carbon thin targets by impact of H{sup 0}, H{sub 2}{sup +} and H{sub 3}{sup +} projectiles at MeV energies; Multiplicite des electrons secondaires emis par des cibles minces de carbone sous l`impact de projectiles H{sup 0}, H{sub 2}{sup +} et H{sub 3}{sup +} d`energie de l`ordre du MeV

    Energy Technology Data Exchange (ETDEWEB)

    Vidovic, Zvonimir [Inst. de Physique Nucleaire, Lyon-1 Univ., 69 - Villeurbanne (France)

    1997-06-24

    This work focuses on the study of the emission statistics of secondary electrons from thin carbon foils bombarded with H{sup 0}, H{sub 2}{sup +} and H{sub 3}{sup +} projectiles in the 0.25 - 2.2 MeV energy range. The phenomenon of secondary electron emission from solids under the impact of swift ions is mainly due to inelastic interactions with target electrons. Phenomenological and theoretical descriptions as well as a summary of the main theoretical models are the subjects of the first chapter. The experimental set-up used to measure event by event the electron emission of the two faces of the thin carbon foils crossed by an energetic projectile is described in the chapter two. In this chapter there are also presented the method and the algorithms used to process experimental spectra in order to obtain the statistical distribution of the emitted electrons. Chapter three presents the measurements of secondary electron emission induced by H{sup 0} atoms passing through thin carbon foils. The secondary electron yields are studied in correlation with emergent projectile charge state. We show the peculiar role of the projectile electron, whether it remains or not bound to the incident proton. The fourth chapter is dedicated to the secondary electron emission induced by H{sub 2}{sup +} and H{sub 3}{sup +} polyatomic ions. The results are interpreted in terms of collective effects in the interactions of the ions with solids. The role of the proximity of the protons, molecular ions fragments, upon the amplitude of these collected effects is evidenced from the study of the statistics of forward emission. The experiments allowed us to shed light on various aspects of atom and polyatomic ion interactions with solid surfaces. (author) 136 refs., 41 figs., 3 tabs.

  2. 弹丸头锥上对称配置的S波段微带天线阵%S-band Microstrip Antenna Array Symmetrically Configured on Projectile Nose Cone

    Institute of Scientific and Technical Information of China (English)

    付强; 曹少琚; 余孝安; 乔飞

    2011-01-01

    针对以前传统的微带共形阵在弹道修正弹和遥测等应用平台上安装困难及抗高过载的问题,提出了一种弹丸头锥上对称配置的S波段微带天线阵.该微带天线阵采用天线单元与微带功分器分离的形式,两个天线单元介质基片焊接在23 mm×30 nm的钢片上,用螺钉固定在头锥上铣削出的小平面上,在头锥两侧对称布置.微带功分器放置在锥体内部,天线单元通过背馈方式与微带功分器连接,进行等幅同相馈电.仿真、测试与试验表明:S波段弹丸头锥上对称配置的抗高过载微带天线阵性能指标优良、安装工艺简单且具有抗高过载能力,该研究成果可应用于各种尺寸的遥测和弹道修正弹的弹载共形微带天线阵设计.%In view of the traditional microstrip conformal antenna array applied on trajectory correction projectile and telemetry platform has difficulties on installation and anti-high overload,a S-band mocrostrip antenna array which was symmetrically configured on projectile nose cone was put forward in this paper. The antenna unit was separate from the microstrip merit minute, two antenna units' medium substrate were welded on 23 mmX30 mm steel disk, with screw retention on the symmetrical facet of the nose cone. Simulation and experiment results indicated that the S-band microstrip antenna array which symmetrically arranged on projectile nose cone had good performance indexes,high overload resistance, and was easy embeded. The research could provide reference to conformal microstrip antenna array design of different sizes telemetry projectile and the trajectory correction projectile.

  3. 某型末制导炮弹全弹道捕获域研究%Research on Total Capture Area of Terminal Guidance Projectile

    Institute of Scientific and Technical Information of China (English)

    赵成旺; 宋卫东; 何伟

    2013-01-01

    At present,the research of the capture capability of terminal guidance projectile(TGP)is concentrated on the study of the instant static capture area on the space-point,and the total capture area can't be calculated.Aiming at this problem,a new concept of total capture area was presented.The component of total capture area was analyzed,and the calculation method was proposed by analyzing the capturing mechanism of TGP based on ballistic theory.The influence of obliquity variety on total capture area parameters such as borderline,portrait length,landscape orientation width and area,was simulated.Simulation result demonstrates that total capture area is sensitive to the variety of obliquity.%目前末制导炮弹捕获能力多关注于在空间某一点瞬时静态捕获域研究,不能解决炮弹所能捕获目标的所有捕获区域大小的问题.针对此情况,提出了全弹道捕获域的概念.通过对桌型末制导炮弹捕获目标机理的分析,基于弹道学理论,分析了全弹道捕获域组成,并给出了全弹道捕获域方法.仿真了弹道倾角变化对于捕获域相关参数,如边界、纵向长度、横向宽度、捕获面积等的影响.结果表明,全弹道捕获域对于弹道倾角变化是敏感的.

  4. Experimental study on structural parameter optimization of tandem explosively-formed projectile charges%串联EFP装药结构参数优化实验研究

    Institute of Scientific and Technical Information of China (English)

    徐浩铭; 顾文彬; 唐勇; 刘建青; 王振雄; 王诤

    2013-01-01

    To realize that hunk fraises can be fast perforated and the perforated depth and width are enough,a new tandem shaped charge structure was proposed by using two same structures of explosively-formed projectile (EFP) shaped charges.And the effects of the structural parameters on the tandem EFP charge penetration power were analyzed.Based on the above analysis,experiments were conducted for tandem EFPs penetrating 45 steel targets under different charge spacings and different initiation delays,respectively.The results show that the tandem EFP charge structure can greatly improve the penetration efficiency of the two-stage tandem shaped charge and it can be used to effectively penetrate hard objects.%为了在大块度障碍物上快速开孔且孔深和孔径符合要求,提出了一种前后两级均为爆炸成形弹丸(EFP)装药的新型串联聚能装药结构.分析了装药结构参数对串联EFP侵彻威力的影响,并在此基础上分别开展了串联EFP装药在不同装药间距与起爆延时条件下侵彻45钢靶实验.实验表明,优化后的串联EFP装药结构使前后两级EFP装药的侵彻效率大大提高,能对硬目标进行有效破孔.

  5. Relativistic exotic nuclei as projectile beams. New perspectives of studies on the properties of nuclei; Relativistische exotische Kerne als Projektilstrahlen. Neue Perspektiven zum Studium der Kerneigenschaften

    Energy Technology Data Exchange (ETDEWEB)

    Geissel, H.

    1997-03-01

    Examinations of the production cross-sections and the kinematics permitted refinement of model concepts of the peripheral reactions in exotic nuclei at energies from 100 to 1000 A MeV. Due to the strong selectivity and resolution achieved it was possible to discover a large number of novel isotopes at the fragment separator FRS, despite the relatively low projectile beam intensities of the SIS. The two twice magic nuclei found, Ni 78 and Sn 100, are particularly interesting, as they could not be measured so far with other experimental systems. Fission of relativistic uranium ions proved to be a particularly successful process yielding many medium-heavy, neutron-rich nuclei. Insight into the structure of light neutron halos could be improved. The superlarge spatial dimensions of the nuclear halos is discussed. (orig./CB) [Deutsch] Die Untersuchungen der Produktionsquerschnitte und der Kinematik fuehr ten zu einer Verfeinerung der Modellvorstellungen der peripheren Kernr eaktionen an exotischen Kernen bei Energien im Bereich von 100- 1000 A MeV. Die hohe Selektivitaet und Aufloesung waren die Voraussetzung, da ss schon bei den vergleichsweise niedrigen Projektilstrahlintensitaete n des SIS eine grosse Anzahl von neuen Isotopen am Fragmentseparator F RS entdeckt werden konnten. Besonders erwaehnenswert sind die beiden d oppelt magischen Kerne Ni 78 und Sn 100, die mit anderen experimentel len Anlagen vorher nicht zugaenglich waren.Die Spaltung relativistisch er Uranionen hat sich als eine besonders ergiebige Quelle fuer mittels chwere neutronenreiche Kerne erwiesen. Die Kenntnisse der Struktur lei chter Neutronen- Halokerne konnten erweitert werden. Die uebergrosse r aeumliche Ausdehnung der Halokerne wurde aufgezeigt.

  6. On the Influence of Fracture Criterion on Perforation of High-Strength Steel Plates Subjected to Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    Tria Djalel Eddine

    2015-06-01

    Full Text Available Artykuł przedstawia numeryczne badania wpływu kryterium pekania materiału na perforacje płyt ze stali pancernej 30PM pociskiem przeciwpancernym 7,6251 mm. Dokonano oceny czterech modeli pekania materiałów plastycznych w celu wyboru najbardziej odpowiedniego z nich. W artykule wykorzystano zmodyfikowany model konstytutywny Johnsona-Cooka (MJC sprzezony z jednym czterech kryteriów pekania: kryterium MJC, kryterium Cockrofta-Lathama (CL, kryterium maksymalnego naprezenia stycznego i kryterium stałego granicznego odkształcenia. Zastosowano trójwymiarowy algorytm w opisie Lagrange’a, zawierajacy zarówno skonczone elementy jak i czastki, z automatyczna konwersja zniekształconych elementów w bezsiatkowe czastki. Wyniki symulacji numerycznej oceniono na postawie porównania z wynikami doswiadczen. Model pekania MJC, sformułowany w przestrzeni trójosiowosci naprezenia i równowaznego odkształcenia plastycznego, pozwolił przewidziec realistycznie obraz pekania materiału i wartosci predkosci resztkowych pocisków. Jednakze wyniki badan wykazały, ze równiez jednoparametrowy model CL, dla którego kalibracji wystarczy jeden prosty test materiałowy, daje porównywalne wyniki z kryterium MJC. Stwierdzono, ze kryterium maksymalnego naprezenia stycznego niepoprawnie opisuje proces tworzenia sie korka. Równiez kryterium stałej wartosci odkształcenia granicznego nie moze byc uzyte do scharakteryzowania procesu niszczenia materiału.

  7. 目标丢失对末制导炮弹末导段弹道特性影响%Influence of Target Missing on Terminal Ballistic Trajectory of Terminal Guidance Projectile

    Institute of Scientific and Technical Information of China (English)

    赵成旺; 宋卫东; 任旭

    2013-01-01

    Target missing and target re-capturing may happen in the terminal ballistic trajectory of terminal guidance projectile because of the factors as jamming and/or weather. To gain the relation between the terminal ballistic trajectory character and the time of target missing, the terminal guidance projectile control model was set up according to small disturbance theory. The trajectory character when missing target and recapturing under different target maneuvering conditions was simulated. The simulation result for the target at uniform motion and uniform varying motion was analyzed, which demonstrated that the target missing during terminal trajectory has remarkable impact to projectile's terminal ballistic trajectory character, especially when the target is in maneuvering.%针对末制导炮弹受光电干扰及天气等因素影响,在末导段出现丢失目标以及丢失后重新捕获目标等情况,依据小扰动原理建立了比例导引模式下末制导炮弹控制模型,获取末制导炮弹的脱靶量、法向过载等与目标丢失时机以及丢失时间长短的解析关系,对目标机动特性不同情况下失去目标及重新捕获目标后的弹道特性进行了仿真,对比分析了目标静止及机动情况下仿真结果中各种指标变化的异同及原因.仿真结果表明,末导段目标丢失会对末制导炮弹弹道特性造成显著影响,尤其是在目标采取机动的情况下.

  8. 弹丸对预开孔混凝土靶体侵彻的实验研究∗%Experimental Investigation on Projectile Penetrating Pre-borehole Concrete Target

    Institute of Scientific and Technical Information of China (English)

    杨世全; 王洪波; 谢若泽; 张方举; 钱立新

    2015-01-01

    According to the design idea of multiple-shaped-charge tandem warhead, target damage by forward warhead was simplified as borehole pre-damage, and the experimental investigation was carried out on projectile penetrating to pre-borehole concrete target in this pa-per. The influence of borehole model of target on projectile penetration capability was analyzed. As a result, the increase of projectile pene-tration depth was followed by increase of borehole amount and depth. Comparatively, the increase of borehole amount is more effective be-cause the increase of borehole amount is equivalent to the increase of damage area of target. The results can provide reference for the design of forward multiple-shaped-charge in tandem warhead.%针对集群聚能串联战斗部设计思想,将前级对目标的破坏简化为开孔预破坏,开展了弹丸对预开孔混凝土靶体的实验研究,分析了靶体开孔形式对弹丸侵彻性能的影响。结果表明,弹丸对预开孔靶体的侵彻深度随靶体开孔数量和开孔深度的增加而增加,相对说来,增加开孔数量相当于增加了靶体破坏面积,对提高后级侵彻能力更为有效。研究结果可为串联战斗部的前级集群聚能装药设计提供参考。

  9. Simulation of the projectile dynamics in granular media∗%运动物体在颗粒物质中的动力学过程及最大穿透深度仿真研究*

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    The three-dimensional (3D) dynamics of a projectile in granular media is simulated using DEM (discrete element method). Periodic boundary conditions are adopted, and the effects of gravity, contact forces, damping and friction are taken into account. The 3D simulation results fit the experiment results very well. Simulation results show that the heaver the projectile, the deeper the penetration depth. The impact depth grows linearly when the projectile quality increases. And when the density of granular media decreases, the penetration depth also increases. Splash of granular particles is also observed in the impact simulation.%  利用离散元法仿真了运动物体在颗粒物质中的三维动力学过程,仿真采用周期边界条件,并考虑了重力、接触力、阻尼力、摩擦力的影响。将仿真结果和相关的三维实验结果进行了对比,两者符合较好。仿真结果表明穿透深度与运动物体的冲击速度、运动物体质量、颗粒介质床的密度均有关系。运动物体质量越大,速度越快,则穿透越深,而且穿透深度和质量呈线性关系。仿真过程较为真实地再现了小颗粒的飞溅现象。

  10. Experimental evaluation of load-time functions due to impact of projectiles onto rigid structures; Experimentelle Untersuchung zur Ermittlung der Last-Zeit-Funktion beim Aufprall von Stosskoerpern auf eine steife Struktur

    Energy Technology Data Exchange (ETDEWEB)

    Ruch, D.; Herrmann, N.; Mueller, H.S. [MPA Karlsruhe (Germany)

    2008-07-01

    Investigations were performed to determine the load-time functions due to the impact of projectiles on a rigid structure. Two different experimental setups were used to study the impact force of aluminium projectiles: a rotating steel target and a massive pendulum construction. Both setups need a continuative processing of measured data. The used filtering concept shows for all experiments up to now more reasonable results than a pure deep-pass data filtering. The applicability of the concept for experiments with changed parameters has to be verified and eventually optimized. In the future of the project the influence of different tank fillings on the load-time functions will be studied. Comparative experiments with the old projectile geometry and the steel target shall be performed in order to allow an improved data evaluation. The experiments will be analysed with numerical methods, including the analytical force behaviour according Riera. [German] Es wurden Untersuchungen zur Ermittlung der Last-Zeit-Funktion beim Aufprall von Stosskoerpern auf eine steife Struktur vorgestellt. Hierbei kommen zwei unterschiedliche Versuchsaufbauten zur Ermittlung der Aufprallkraft der verwendeten Aluminiumprojektile zum Einsatz. Dies sind ein drehbares Stahltarget und eine massive Pendelkonstruktion. Beide Versuchsaufbauten erfordern eine weiterfuehrende Bearbeitung der Messdaten, da Eigenschwingungen der Zielkoerper nicht vollstaendig eliminiert werden koennen. Hierzu kommen verschiedene Filterungen zum Einsatz. Das vorgestellte alternative Filterkonzept zeigt fuer die bisherigen Versuche sinnvollere Ergebnisse als eine reine Tiefpassfilterung der Daten. Die Anwendbarkeit des Konzepts auf Versuche mit veraenderten Parametern ist zu verifizieren und gegebenenfalls zu optimieren. Im weiteren Verlauf des Projekts soll der Einfluss unterschiedlicher Tankfuellungen auf die Last-Zeit-Funktion untersucht werden. Ferner wird angestrebt Vergleichsversuche mit der alten

  11. 某新型制导炮弹内弹道性能研究%Study on Interior Ballistic Performance for a New Type of Guided Projectile By Gun

    Institute of Scientific and Technical Information of China (English)

    蔡灿伟; 张玉荣; 陶辰立; 王涛

    2014-01-01

    考虑到气缸张开式尾翼启动时机与炮弹的内弹道性能密切相关,对某新型制导炮弹内弹道性能进行了研究,建立了内弹道一维两相流模型并采用了两阶精度的MacCormack差分格式对模型进行了仿真,得到了膛压、弹丸速度等随时间的变化规律曲线,分析了药厚、火药燃烧规律、弹丸阻力系数等因素对内弹道性能的影响。研究结果为进一步分析该新型制导炮弹气缸张开式尾翼气缸压力的变化规律提供了理论依据。%The interior ballistic performance for the guided projectile is studied and the one-dimensional two-phase flow model is established considered the important relationship between the cylinder-open fin's setup time and the interior ballistic performance. They are numerical simulated by two step MacCormack scheme such as the gun pressure and the projectile velocity. And it is analyzed that the powder thickness, powder burning law projectile resistance coefficient and other factors impact on the interior performance. The results provide the theoretical basis for analyzing the pressure of cylinder-open fin.

  12. Research on Projectile Impacting Target by Means of Light-gas Gun With High-speed Photography%利用轻气炮进行侵彻试验的高速摄影法探索

    Institute of Scientific and Technical Information of China (English)

    高航; 张继春; 肖正学; 郭学彬; 陈星明; 吝曼卿

    2011-01-01

    To study effectual observation way of impact experiment with the light-gas gun,a high-speed photography system applied to light-gas gun was designed. The setup of photography system, safety protect and optical design were given. Aiming at the conditions of projectile impacting target vertically and obliquely, the flight attitude of projectile before impacting target, the penetration process after impacting target and the motion state of pieces of concrete target were studied by the experiment. The result shows that the variations of velocity and attitude of projectile in the whole impact process and the damage state of target can be caught by high-speed photography in the impact process of light-gas gun.%为获取轻气炮冲击实验有效的观测方法,设计了一种用于一级轻气炮的高速摄影系统,给出了摄影系统的布王、安全防护和光路设计.利用该实验系统研究了弹丸垂直冲击靶体和斜冲击靶体情况下,弹丸碰靶前的飞行姿态、碰靶后的侵彻过程以及混凝土靶体飞溅物的运动状态等,结果表明高速摄影方法在轻气炮进行冲击过程中能够捕捉到弹丸在整个冲击过程中速度和姿态的连续变化情况以及靶体破坏状态等大量信息.

  13. Simulation and Dynamic Analysis of Terminal Guide Projectile' Inertial Guide Gyro%某型末制导炮弹惯导陀螺动力学分析与仿真

    Institute of Scientific and Technical Information of China (English)

    刘炳辰; 宋卫东; 寇玺; 文海波

    2011-01-01

    At present domestic and overseas scholars research the inertial guide gyro and the terminal guide projectile as a single rigid body. Angles of external and internal framework are deduced by means of the conversion relationship among the body of the terminal guide projectile coordinate system, the inertial guide gyro coordinate system and the ground coordinate system, which can not directly reflect the law in the motion of inertial guide gyro' external and internal framework. In order to research the law and set up the terminal guide projectile' kinetic angle model under multi-body systems dynamics condition. Firstly hypothesis was put forward and new reference frames were found, secondly analyzing the motion of the inertial guide gyro using theorem of moment of momentum, establishing kinetic models of the inertial guide gyro, thirdly employing Matlab/Simulink software to work out the procedure, calculation was carried out. Eventually more precise kinetic angle models are established and the ballistic track of the terminal guide projectile under multi-body systems dynamics condition is described accurately.%目前国内外学者将惯导陀螺连同末制导炮弹弹体视作单刚体来研究,对于惯导陀螺内外框摆动角的确定是通过弹体坐标系、惯导陀螺坐标系和地面坐标系之间的转换关系推导出来的,并不能直接反应惯导陀螺内外框摆动的动力学规律.为了揭示惯导陀螺内外框摆动角变化的内在规律,得到多刚体条件下末制导炮弹角运动模型,首先进行基本假设、建立坐标系,其次运用动量矩定理对内外框摆动进行分析,建立了内外框摆动角的动力学模型,再次应用Matlab/Simulink软件编制程序,对该数学模型进行了仿真计算,最终得到了该型末制导炮弹更加精确的角运动模型,揭示了其在多刚体条件下的运动规律.

  14. 自然风对旋转弹丸外弹道性能影响的仿真研究%Simulation and Study of Effect of Natural Wind on External Trajectory Performance of Spinning Projectile

    Institute of Scientific and Technical Information of China (English)

    冯德朝; 张方方; 胡春晓

    2012-01-01

    为研究自然风对旋转弹丸外弹道性能的影响,基于坐标变换理论考虑了地球曲率变化对刚体弹道模型的作用,分析了自然风对各气动力和气动力矩的影响,建立了非标准条件下的刚体外弹道模型.应用该模型对某105mm榴弹不同风速、风向下的外弹道过程进行仿真,结果表明,自然风对飞行弹丸的攻角姿态有较大影响,进而影响弹丸的射程和方向偏移量;自然风对弹丸攻角姿态的影响在弹丸飞行的初始阶段风速大小起主要作用,而在弹丸飞行的中间阶段则是风矢方向起主要作用.%To study the effect of natural wind on external trajectory performance of spinning projectile, effect of earth curvature was analyzed based on the theory of coordinate transformation, the effect of natural wind on aerodynamic force and moment was analyzed. The external trajectory model was established under nonstandard environment. The external trajectory of a 105mm shrapnel at different wind speeds and wind orientation was simulated by use of this model. The calculated results shows that the attack angle of projectile is crucially affected by natural wind which eventually changes the trajectory of projectile. The size of wind speed plays an important role in the effect of natural wind on the dynamical stability at the beginning stage of flying projectile, while at the midway stage the main factor is changed to the direction of wind.

  15. 多幕光学法测量弹丸炸点坐标及误差分析%Measurement of Projectile Burst Coordinates by Using Multi-Screen Optical Method and Its Error Analysis

    Institute of Scientific and Technical Information of China (English)

    李翰山; 雷志勇

    2012-01-01

    针对飞行弹丸对空中目标近炸炸点位置测量,提出了多幕光学法测量技术.根据试验特点,分析了多光幕交汇测量弹丸炸点位置存在的问题,研究了采用侧向相机辅助多光幕交汇测量技术.通过相机采集到的炸点图像,建立相机、模拟目标和多光幕交汇光幕阵列空间几何计算模型.利用弹丸的飞行轨迹和弹丸炸点图像平面坐标,研究了弹丸炸点侧向空间坐标的计算方法和多光幕交汇测量系统二维坐标修正原理,给出了弹丸炸点坐标计算函数.利用微分法从交汇光幕夹角、光幕幕厚、测时和测距等方面分析测量误差.经计算分析,模拟目标中心高度小于50 m时,炸点三维坐标的误差小于40 mm.%The multi-screen optical method is put forward to solve the problem of three-direction coordinate measurement when the flying projectile gets close to object and explodes in the high altitude. According to experiment characteristic, the demerits of multi-screen across target are pointed out and the technology of using lateral layout area camera to assistant multi-screen across target is studied. The mathematics geometry model on camera, simulating object and multi-screen across target is set up based on projectile burst image acquired by lateral camera. The lateral coordinates calculation method and the modified principle of two-dimensional coordinates of multiscreen across target are studied and analyzed by using projectile flying contrail and its plane coordinates of burst image. The function of three-dimensional projectile burst coordinates is given. The differential method is applied to analyze their coordinate' s errors, which come from the angle of intersection screen, the thick of screen, the measurement time, ranging and so on. Coordinate errors will be less than 40 mm when the height of simulating object is less than 50 m by theoretical analysis and calculation.

  16. Chlamydia Testing

    Science.gov (United States)

    ... Amplification Test (NAAT); Chlamydia trachomatis Culture; Chlamydia trachomatis DNA Probe Related tests: Gonorrhea Testing , HIV Antibody and HIV Antigen , Syphilis Tests , Herpes Testing , HPV Test , Trichomonas Testing All content on Lab Tests Online has ...

  17. Syphilis Test

    Science.gov (United States)

    ... Gonorrhea Testing , Chlamydia Testing , Herpes Testing , HPV Test , Trichomonas Testing , CSF Analysis All content on Lab Tests ... testing ( polymerase chain reaction, PCR )--this test detects genetic material from the bacteria in the sample from ...

  18. Benchmarking of calculated projectile fragmentation cross-sections using the 3-D, MC codes PHITS, FLUKA, HETC-HEDS, MCNPX_HI, and NUCFRG2

    Science.gov (United States)

    Sihver, L.; Mancusi, D.; Niita, K.; Sato, T.; Townsend, L.; Farmer, C.; Pinsky, L.; Ferrari, A.; Cerutti, F.; Gomes, I.

    several particle and heavy-ion MC transport codes exist, e.g. Particle and Heavy-Ion Transport code System (PHITS), High Energy Transport Code-Human Exploration and Development of Space (HETC-HEDS), SHIELD-HIT, GEANT4, FLUKA, MARS, and MCNPX. In this paper, we present an extensive benchmarking of the calculated projectile fragmentation cross-sections from the reactions of 300-1000MeV/u28Si, 40Ar, and 56Fe on polyethylene, carbon, aluminum, and copper targets (relevant to space radioprotection) using PHITS, FLUKA, HETC-HEDS, and MCNPX, against measurements. The influence of the different models used in the different transport codes on the calculated results is also discussed. Some measured cross-sections are also compared to the calculated cross-sections using NUCFRG2, which are incorporated in the 1-dimensional, deterministic radiation transport code HZETRN.

  19. Gonorrhea Test

    Science.gov (United States)

    ... gonorrhoeae Culture; Neisseria gonorrhoeae Gram Stain; Neisseria gonorrhoeae DNA Probe Related tests: Chlamydia Testing , HIV Antibody and HIV Antigen , Syphilis Tests , Herpes Testing , HPV Test , Trichomonas Testing All content on Lab Tests Online has ...

  20. 滑块机构下高旋弹头的姿态角速度控制%Control Attitude Angular Velocity for High-rolling Projectile by Moving-Mass Framework

    Institute of Scientific and Technical Information of China (English)

    李永博; 郭治

    2009-01-01

    The definitions of dynamic and static equations with the moving-mass framework for high-rolling projectile were proposed; the dynamic gesture equation was established based on a bi-moving mass model, which is abbreviated by linearization method; the abbreviated equation was described as the standard state space form, the feedback control law was designed according to satisfactory control theory, to reach control tracking the angle velocities at yaw and pitch rotation directions; the tracking angular velocity for high-spin projectile with moving-mass framework was simulated. The simulated result shows the proposed algorithm is effective and proyides a necessary reference for practical engineering.%针对高旋弹头滑块控制的特点,提出了动态方程和静态方程的概念;以双滑块机构为模型,建立了动态姿态动力学方程,运用线性化手段将方程化简;并列写成标准的状态空间形式,以满意控制理论设计了反馈控制律,以达到控制俯仰、偏航角速度的目的;针对某型高旋弹进行了仿真研究.仿真结果表明控制效果明显,为实际工程应用提供了必要借鉴.

  1. Susceptibility Testing

    Science.gov (United States)

    ... page helpful? Also known as: Sensitivity Testing; Drug Resistance Testing; Culture and Sensitivity; C & S; Antimicrobial Susceptibility Formal name: Bacterial and Fungal Susceptibility Testing Related tests: Urine Culture ; ...

  2. Design and Testing of Braided Composite Fan Case Materials and Components

    Science.gov (United States)

    Roberts, Gary D.; Pereira, J. Michael; Braley, Michael S.; Arnold, William a.; Dorer, James D.; Watson, William R/.

    2009-01-01

    Triaxial braid composite materials are beginning to be used in fan cases for commercial gas turbine engines. The primary benefit for the use of composite materials is reduced weight and the associated reduction in fuel consumption. However, there are also cost benefits in some applications. This paper presents a description of the braided composite materials and discusses aspects of the braiding process that can be utilized for efficient fabrication of composite cases. The paper also presents an approach that was developed for evaluating the braided composite materials and composite fan cases in a ballistic impact laboratory. Impact of composite panels with a soft projectile is used for materials evaluation. Impact of composite fan cases with fan blades or blade-like projectiles is used to evaluate containment capability. A post-impact structural load test is used to evaluate the capability of the impacted fan case to survive dynamic loads during engine spool down. Validation of these new test methods is demonstrated by comparison with results of engine blade-out tests.

  3. 平头弹对接触式双层靶板破坏模式的研究%Perforation Modes of Double-layered Plates Struck by a Blunt Rigid Projectile

    Institute of Scientific and Technical Information of China (English)

    孙章腾; 刘兵

    2015-01-01

    本文是研究接触式双层靶板对平头弹的抗侵彻性能,实验发现接触式双层靶的弹道极限高于相同厚度的单层靶,认为提高其弹道极限的原因是发生较大的弯曲变形,需要耗散更多的能量,塞块增大靶板的有效厚度。以能量守恒定理及Chen和Li模型为理论基础,提出平头弹贯穿接触式双层金属靶后的剩余速度的计算公式。在穿甲过程中,考虑塞块对终点弹道性能产生的影响,对相关的平头弹穿甲Weldox 700 E系列钢靶的试验数据进行分析比较。%The thesis aims at exploring the perforation of double-layered plates in contact struck by a blunt rigid projectile.The experiment shows that the ballistic limit of a double-layered target is higher than a monolithic target’s.The thesis considers that the higher ballistic limit lies in the great bending deformation which requires more energy consumptions and the plug has extended the effective thickness of target.Based on the laws of conservation of energy and the model of Chen and Li,the calculation formula of residual velocity can be put forward after the blunt projectile penetrates the double-layered plate.In the process of armor-piercing, considering about the influence of the plug on the property of terminal ballistic limit,the thesis has compared and analyzed the relevant experimental data about blunt projectile piercing the plates from Weldox 700E series.

  4. AN ANALYTICAL MODEL FOR PENETRATION INTO CYLINDRICAL METALLIC THICK TARGET BY RIGID SHARP-NOSED PROJECTILES%刚性尖头弹侵彻圆柱形金属厚靶分析模型

    Institute of Scientific and Technical Information of China (English)

    宋殿义; 刘飞; 蒋志刚

    2013-01-01

    考虑金属厚靶侧面自由边界的影响,研究了刚性尖头弹侵彻有限平面尺寸金属厚靶问题.基于有限柱形空腔膨胀理论和线性硬化材料模型,得到了空腔壁径向压力的解析式,建立了刚性尖头弹侵彻有限直径圆柱形金属厚靶工程模型.与试验和数值模拟比较表明,该文工程模型计算精度很好.基于所建立的工程模型,研究了靶板半径对侵彻深度和侵彻阻力的影响,结果表明:当靶板与弹丸半径比值小于20时,靶板半径对侵彻阻力和侵彻深度有显著影响,不能按无限尺寸靶板计算;当靶板与弹丸半径比值大于20时,靶板半径对侵彻阻力和侵彻深度影响较小,可近似按无限尺寸靶计算.%The penetration of thick mental targets with finite planner dimensions by a rigid sharp-nose was investigated in the consideration of the lateral free boundary of the target. Based on the Finite Cylindrical Cavity Expansion (FCCE) theory and the linear strain-hardening material model, analytical solutions of radial pressure on the cavity wall were obtained, and an engineering model for rigid sharp-nosed projectile penetration into cylindrical thick metal targets was presented. The penetration depths from the present model are in a good agreement with those from the published ballistic experiments and numerical simulation. Based on the model, the influence of a target radius on penetration depth and penetration resistance was studied. The results show that the penetration resistance and the penetration depth are obviously affected by the ratio of the target radius to the projectile radius when the ratio is less than 20, they can not be calculated as an unlimited-size target. When the ratio of the target radius to the projectile radius is larger than 20, the target radius has less effects on the penetration depth and penetration resistance, that can be approximately calculated as an unlimited-size target.

  5. Test plan :

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Stephen F.

    2013-05-01

    This test plan is a document that provides a systematic approach to the planned testing of rooftop structures to determine their actual load carrying capacity. This document identifies typical tests to be performed, the responsible parties for testing, the general feature of the tests, the testing approach, test deliverables, testing schedule, monitoring requirements, and environmental and safety compliance.

  6. Effects of Liner Curvature Radius on Formation of Double-Layered Spherical Segment Charge Liner into Tandem Explosively Formed Projectile (EFP)%曲率半径对双层球缺罩形成串联爆炸成型弹丸的影响

    Institute of Scientific and Technical Information of China (English)

    郑宇; 王晓鸣; 李文彬; 李伟兵

    2009-01-01

    为了研究曲率半径对串联爆炸成型弹丸(EFP)形成的影响,利用有限元软件AUTODYN,对双层球缺罩串联EFP的成型过程进行了数值仿真,在此基础上分析了双层球缺罩串联EFP的形成机理,探讨了曲率半径对串联EFP的影响规律.开展了双层药型罩EFP形成的实验研究,得到了串联EFP形成过程的X光照片,仿真和试验结果比较一致.仿真与试验结果都表明:双层球缺罩可以形成前后分离的串联EFP,双层球缺罩的曲率半径对串联EFP的速度、外形和长径比有较大影响.%In order to study the influences of liner curvature radius on the formation of double-layer shaped charge liner (DLSCL) into tandem explosively formed projectile(EFP),the numerical simulations on the mechanical phenomenon of DLSCL forming into tandem EFP were carried out by using two-dimensional finite element dynamic code AUTODYN.The formation mechanisms of DLSCL and the influence of curvature radius on the formation of DLSCL were studied.After tests on the formation of DLSCL were performed,the X-ray pictures were obtained.Comparisons between experimental results and numerical simulation results show a good agreement.It can be concluded from the results that DLSCL can form tandem EFP and the liner curvature radius has great influence on the velocity,shape and l/D radius of tandem EFP.

  7. Prenatal Tests

    Science.gov (United States)

    ... Close X Home > Pregnancy > Prenatal care > Prenatal tests Prenatal tests E-mail to a friend Please fill ... even if you’re feeling fine. What are prenatal tests? Prenatal tests are medical tests you get ...

  8. Pinworm test

    Science.gov (United States)

    Oxyuriasis test; Enterobiasis test; Tape test ... diagnose this infection is to do a tape test. The best time to do this is in ... to determine if there are eggs. The tape test may need to be done on 3 separate ...

  9. A Novel Apoptosis Correlated Molecule: Expression and Characterization of Protein Latcripin-1 from Lentinula edodes C91–3

    OpenAIRE

    Min Huang; Wei Zhang; Lei Liu; Jing Cao; Anhong Ning; Yongzhi Lun; Xiaoli Wang; Wenchang Sun; Xingyun Li; Mintao Zhong; Ben Liu

    2012-01-01

    An apoptosis correlated molecule—protein Latcripin-1 of Lentinula edodes C91-3—was expressed and characterized in Pichia pastoris GS115. The total RNA was obtained from Lentinula edodes C91–3. According to the transcriptome, the full-length gene of Latcripin-1 was isolated with 3'-Full Rapid Amplification of cDNA E...

  10. Potential role of lncRNA cyp2c91-protein interactions on diseases of the immune system

    OpenAIRE

    Suravajhala, Prashanth; Kogelman, Lisette J. A.; Mazzoni, Gianluca; Kadarmideen, Haja N

    2015-01-01

    With unprecedented increase in next generation sequencing technologies, there has been a persistent interest on transcript profiles of long non-coding RNAs (lncRNAs) and protein-coding genes forming an interaction network. Apart from protein–protein interaction (PPI), gene network models such as Weighted Gene Co-expression Network Analysis (WGCNA) are used to functionally annotate lncRNAs in identifying their potential disease associations. To address this, studies have led to characterizing ...

  11. Testing? Testing? In Literature?

    Science.gov (United States)

    Purves, Alan C.

    The assumptions behind secondary school literature course tests--whether asking students to recall aspects of literary works, to relate literary works to each other, or to analyze unfamiliar literary works--are open to question. They fail to acknowledge some of the most important aspects of literature which, if properly taught, should provide a…

  12. Test Under Test

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China’s national college entrance examination, regarded as a make-or-break test by many students, leaves much to be desired “We’ve bribed the exam supervisors, paying each one 20,000 yuan. They will make everything go smooth during the exams,” Li Feng, a teacher from No.2 High School in

  13. Research on Separating and Correcting Firing Errors of One Dimension Trajectory Correction Projectile Fired by Shipborne Gun%舰炮一维弹道修正弹射击误差分离和校正研究

    Institute of Scientific and Technical Information of China (English)

    黄义; 汪德虎; 余家祥; 王连柱; 解维河

    2012-01-01

    由于工作原理不同,传统无控弹射击校正方法不适用于一维弹道修正弹.分析了舰炮使用一维弹道修正弹射击误差构成和射击观测特点,提出一维弹道修正弹射击校正新方法,首先通过修正机构不工作,利用观测弹着点相对预测弹着点偏差平均值校正火控设备预测弹着点误差;然后利用修正弹正常工作时观测弹着点相对目标(或提前点)偏差平均值校正修正机构误差.假设各误差值,通过解弹道方程仿真计算表明,该射击校正方法能够显著提高射击精度.%The conventional firing correction method of bomb without control is not fitting for one dimension trajectory correction projectile because their work theory are different. Firing errors and firing detection were analyzed when shipborne gun fired correction projectile, and the new firing correction method was demonstrated. Firstly, the forecasting point of fall error of fire control equipment was corrected with the average deviation between detecting point of fall and forecasting point of fall when damping ring didn't work. Secondly, the correcting error was corrected with the average deviation between detecting point of fall and target or predicted point when damping ring work normally. It is proved that the new firing correction method can improve firing accuracy by simulating with computing trajectory equation and supposing every firing error data.

  14. Modeling and simulation of rigid body external trajectory of spinning projectile under nonstandard conditions%非标准条件下旋转弹丸刚体外弹道的建模与仿真

    Institute of Scientific and Technical Information of China (English)

    侯健; 张方方

    2012-01-01

    为研究非标准条件下高速旋转弹丸的刚体外弹道性能,基于坐标变换理论建立了地球曲率影响下的外弹道数学模型,分析了自然风对弹丸气动力及气动力矩的作用,并在考虑气温气压及重力加速度变化的基础上得到了非标准务件下旋转弹丸的刚体外弹道模型.利用该模型对某105 mm榴弹外弹道进行仿真,结果表明:地球曲率引起旋转弹丸外弹道性能参数值少量增加,且增加量随弹丸射程的增大而增加,验证了自然风对弹丸动态稳定性有较大影响,进而影响弹丸的各弹道参数的结论.%To study the rigid body external trajectory performance of spinning projectile under non-standard conditions,the effect of natural wind on earth curvature was analyzed. Moreover,a rigid body external trajectory model was established according to the variations in atmospheric pressure,temperature and acceleration of gravity. The simulation was carried out on the external trajectory of a 105 mm shrapnel by this model. The calculated results show that the external trajectory performance parameters are increased with the fire range by earth curvature,thereby verifying the influence of natural wind upon the dynamical stability of the projectile,which further affects the external trajectory performance parameters.

  15. Study of secondary electron emission from thin carbon targets with swift charged particles: heavy ions, hydrogen ions; Etude experimentale de l`emission electronique secondaire de cibles minces de carbone sous l`impact de projectiles rapides: ions lourds, ions hydrogene (atomiques, moleculaires ou sous forme d`agregats)

    Energy Technology Data Exchange (ETDEWEB)

    Billebaud, A.

    1995-07-12

    The main subject of this work is the study of electron emission from the two surfaces of thin solid targets bombarded with swift charged particles. The slowing down of swift ions in matter is mainly due to inelastic interaction with target electrons (ionization, excitation): the energy transfer to target electrons is responsible for the secondary electron emission process. The phenomenological and theoretical descriptions of this phenomena are the subject of the first chapter. We focused on secondary electron emission induced by different kind of projectiles on thin carbon foils. In chapter two we describe hydrogen cluster induced electron emission measurement between 40 and 120 keV/proton. These projectiles, composed of several atoms, allowed us to study and highlight collective effects of the electron emission process. We extended our study of electron emission to molecular (H{sub 2}{sup +}, H{sub 3}{sup +}) and composite (H{sup -}, H{sup 0}) projectiles at higher energies (<= 2 MeV): we have designed an experimental set-up devoted to electron emission statistics measurements which allowed us to study, among others things, the role of projectile electrons in secondary electron emission. This experiment is described in the third chapter. Finally, the fourth chapter describes new measurements of electron emission induced by energetic (13 MeV/u) and highly charged argon ion provided by the medium energy beam line (SME) of GANIL (Caen), which have been analyzed in the framework of a semi-empirical model of secondary electron emission. This set of experiments brings new results on composite projectile interaction with matter, and on the consequences of high energy deposition in solids. (author).

  16. Design and Construction of a One-Stage Gas Gun for High Velocity Impact Tests

    Directory of Open Access Journals (Sweden)

    Gamboa-Castellanos Ricardo Alberto

    2015-03-01

    Full Text Available High impact tests are characterized by a projectile traveling at high speed as well as complex events such as flying fragments due to the velocity at which the impact occurs; however, these tests have become increasingly popular due to the need for more stringent protective material requirements nowadays. In this paper, the design and construction of a one-stage light gas gun for ballistic testing is presented. This particular design is characterized by its simplicity, excellent performance at low cost and compact dimensions, when compared to commercial systems, presenting an affordable option for materials characterization for high velocity impact tests. The results are completed with the characterization of an armor grade material, obtaining the ballistic limit of the material, as well as demonstrating the effectiveness and versatility of the equipment.

  17. Ballistic Impact Testing of Aluminum 2024 and Titanium 6Al-4V for Material Model Development

    Science.gov (United States)

    Pereira, J. Michael; Revilock, Duane M.; Ruggeri, Charles R.; Emmerling, William C.; Altobelli, Donald J.

    2012-01-01

    An experimental program is underway to develop a consistent set of material property and impact test data, and failure analysis, for a variety of materials that can be used to develop improved impact failure and deformation models. Unique features of this set of data are that all material property information and impact test results are obtained using identical materials, the test methods and procedures are extensively documented and all of the raw data is available. This report describes ballistic impact testing which has been conducted on aluminum (Al) 2024 and titanium (Ti) 6Al-4vanadium (V) sheet and plate samples of different thicknesses and with different types of projectiles, one a regular cylinder and one with a more complex geometry incorporating features representative of a jet engine fan blade.

  18. Experimental and Modeling Studies of Crush, Puncture, and Perforation Scenarios in the Steven Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, K S; Chidester, S K; Forbes, J W; Garcia, F; Greenwood, D W; Switzer, L L; Tarver, C M

    2002-06-28

    The Steven test and associated modeling has greatly increased the fundamental knowledge of practical predictions of impact safety hazards for confined and unconfined explosive charges. Building on a database of initial work, experimental and modeling studies of crush, puncture, and perforation scenarios were investigated using the Steven impact test. The descriptions of crush, puncture, and perforation arose from safety scenarios represented by projectile designs that ''crush'' the energetic material or either ''puncture'' with a pinpoint nose or ''perforate'' the front cover with a transportation hook. As desired, these scenarios offer different aspects of the known mechanisms that control ignition: friction, shear and strain. Studies of aged and previously damaged HMX-based high explosives included the use of embedded carbon foil and carbon resistor gauges, high-speed cameras, and blast wave gauges to determine the pressure histories, time required for an explosive reaction, and the relative violence of those reactions, respectively. Various ignition processes were modeled as the initial reaction rate expression in the Ignition and Growth reaction rate equations. Good agreement with measured threshold velocities, pressure histories, and times to reaction was calculated for LX-04 impacted by several projectile geometries using a compression dependent ignition term and an elastic-plastic model with a reasonable yield strength for impact strain rates.

  19. Coombs test

    Science.gov (United States)

    Direct antiglobulin test; Indirect antiglobulin test ... No special preparation is necessary for this test. ... There are two types of the Coombs test: Direct Indirect The ... that are stuck to the surface of red blood cells. Many diseases ...

  20. Coombs test

    Science.gov (United States)

    Direct antiglobulin test; Indirect antiglobulin test; Anemia - hemolytic ... No special preparation is necessary for this test. ... There are 2 types of the Coombs test: Direct Indirect The direct ... that are stuck to the surface of red blood cells. Many diseases ...